Showing posts with label Psychology. Show all posts
Showing posts with label Psychology. Show all posts

Wednesday 22 March 2023

Parkinson Disease

Parkinson disease (PD) is one of the most common neurologic disorders, affecting approximately 1% of individuals older than 60 years and causing progressive disability that can be slowed, but not halted, by treatment. The 2 major neuropathologic findings in Parkinson disease are loss of pigmented dopaminergic neurons of the substantia nigra pars compacta and the presence of Lewy bodies and Lewy neurites.

Signs and symptoms

Initial clinical symptoms of Parkinson disease include the following:

  • Tremor
  • Subtle decrease in dexterity
  • Decreased arm swing on the first-involved side
  • Soft voice
  • Decreased facial expression
  • Sleep disturbances
  • Rapid eye movement (REM) behavior disorder (RBD; a loss of normal atonia during REM sleep)
  • Decreased sense of smell
  • Symptoms of autonomic dysfunction (eg, constipation, sweating abnormalities, sexual dysfunction, seborrheic dermatitis)
  • A general feeling of weakness, malaise, or lassitude
  • Depression or anhedonia
  • Slowness in thinkin

Onset of motor signs include the following:

  • Typically asymmetric
  • The most common initial finding is a resting tremor in an upper extremity
  • Over time, patients experience progressive bradykinesia, rigidity, and gait difficulty
  • Axial posture becomes progressively flexed and strides become shorter
  • Postural instability (balance impairment) is a late phenomenon

Nonmotor symptoms

Nonmotor symptoms are common in early Parkinson disease. Recognition of the combination of nonmotor and motor symptoms can promote early diagnosis and thus early intervention, which often results in a better quality of life.


Parkinson disease is a clinical diagnosis. No laboratory biomarkers exist for the condition, and findings on routine magnetic resonance imaging and computed tomography scans are unremarkable.

Clinical diagnosis requires the presence of 2 of 3 cardinal signs:

  • Resting tremor
  • Rigidity
  • Bradykinesia


The goal of medical management of Parkinson disease is to provide control of signs and symptoms for as long as possible while minimizing adverse effects.

Symptomatic drug therapy

  • Usually provides good control of motor signs of Parkinson disease for 4-6 years
  • Levodopa/carbidopa: The gold standard of symptomatic treatment
  • Monoamine oxidase (MAO)–B inhibitors: Can be considered for initial treatment of early disease
  • Other dopamine agonists (eg, ropinirole, pramipexole): Monotherapy in early disease and adjunctive therapy in moderate to advanced disease
  • Anticholinergic agents (eg, trihexyphenidyl, benztropine): Second-line drugs for tremor only

Treatment for nonmotor symptoms

  • Sildenafil citrate (Viagra): For erectile dysfunction
  • Polyethylene glycol: For constipation
  • Modafinil: For excessive daytime somnolence
  • Methylphenidate: For fatigue (potential for abuse and addiction)

Deep brain stimulation

  • Surgical procedure of choice for Parkinson disease
  • Does not involve destruction of brain tissue
  • Reversible
  • Can be adjusted as the disease progresses or adverse events occur
  • Bilateral procedures can be performed without a significant increase in adverse events


Before the introduction of levodopa, Parkinson disease caused severe disability or death in 25% of patients within 5 years of onset, 65% within 10 years, and 89% within 15 years. The mortality rate from Parkinson disease was 3 times that of the general population matched for age, sex, and racial origin. With the introduction of levodopa, the mortality rate dropped approximately 50%, and longevity was extended by many years. This is thought to be due to the symptomatic effects of levodopa, as no clear evidence suggests that levodopa stems the progressive nature of the disease.

The American Academy of Neurology notes that the following clinical features may help predict the rate of progression of Parkinson disease :
Older age at onset and initial rigidity/hypokinesia can be used to predict (1) a more rapid rate of motor progression in those with newly diagnosed Parkinson disease and (2) earlier development of cognitive decline and dementia; however, initially presenting with tremor may predict a more benign disease course and longer therapeutic benefit from levodopa
A faster rate of motor progression may also be predicted if the patient is male, has associated comorbidities, and has postural instability/gait difficulty (PIGD)
Older age at onset, dementia, and decreased responsiveness to dopaminergic therapy may predict earlier nursing home placement and decreased survival
Patient Education

Patients with Parkinson disease should be encouraged to participate in decision making regarding their condition. In addition, individuals and their caregivers should be provided with information that is appropriate for their disease state and expected or ongoing challenges. Psychosocial support and concerns should be addressed and/or referred to a social worker or psychologist as needed.

Prevention of falls should be discussed. The UK National Institute for Health and Clinical Excellence has several guidance documents including those for patients and caregivers.

Other issues that commonly need to be addressed at appropriate times in the disease course include cognitive decline, personality changes, depression, dysphagia, sleepiness and fatigue, and impulse control disorders. Additional information is also often needed for financial planning, insurance issues, disability application, and placement (assisted living facility, nursing home).

Sunday 26 January 2020

The Play Theory of Hunter-Gatherer Egalitarianism.

Play counters the tendency to dominate, in humans and in other mammals.

Anthropologists who have trekked to isolated regions of the world to observe hunter-gatherer societies—whether in Africa, Asia, South America or elsewhere—have consistently been impressed by the egalitarian nature of those societies (e.g. Ingold, 1999). The people live in small self-governing bands of about 20 to 50 people per band. They are nomadic, moving from place to place to follow the available game and edible vegetation.

Anthropologists who have trekked to isolated regions of the world to observe hunter-gatherer societies—whether in Africa, Asia, South America or elsewhere—have consistently been impressed by the egalitarian nature of those societies (e.g. Ingold, 1999). The people live in small self-governing bands of about 20 to 50 people per band. They are nomadic, moving from place to place to follow the available game and edible vegetation.

Wherever else we look in the human world, outside of band hunter-gatherers, we see hierarchical structures, in which some people dominate others. Pre-state agrarian tribes are headed by chiefs; modern governments are headed by leaders, elected or not, that have the power to dominate.  We see hierarchy in the workplace, where bosses tell employees what to do. We see it in gangs and in all sorts of formal or informal gatherings, especially of boys and men, who jockey, sometimes violently, for dominance. We see it in schools, where principals tell teachers what to do and teachers tell students what to do. We see it in families where parents dominate children. We also see dominance hierarchies almost everywhere we look in other primates, with alpha individuals (generally males) on top and frequent fighting for status.

It would seem from all this that we humans, or more generally all of us primates, are predisposed genetically to live in dominance hierarchies in which individuals, especially males, more or less continuously strive to move up in the hierarchy. But if that is so, then how do hunter-gatherers manage to live in their egalitarian way? Genes can’t account for that difference. Indeed, people just a generation or so away from being hunter-gatherers, who now live in agricultural societies, often quickly lose their egalitarian tendencies and fall into dominance patterns.


Tuesday 18 June 2019

Magic Mushrooms could replace Anti-depressants!

I started reading this article in the Indepedent with a curious mind! Interest in the potential medical uses for psychedelics, such as “magic mushrooms” and LSD, has rapidly increased in recent years, leading to the opening of the world’s first formal center for psychedelics research in April — and the center’s leader is already prepared to make a bold prediction about the future of psychedelics in medicine. The ideas are bloomed since the cannabis oil became a prescribed medicine recently.

Emotional Release

Carhart-Harris is currently leading a Centre for Psychedelic Research trial to compare the ability of psilocybin, or “magic,” mushrooms and leading antidepressants to treat depression.

He told The Independent that so far, participants are reporting that the psilocybin leaves them feeling like they’ve experienced an emotional “release,” while patients often criticize antidepressants for making them feel like their emotions are “blunted.”

Wishful Thinking

Given the ‘positive’ feedback from study participants and psilocybin mushrooms’ extremely low risk for overdose or addiction, it’s not hard to see why Carhart-Harris is optimistic that doctors will soon be able to use psychedelics to treat patients. Although, we know that the ‘magic’ mushrooms are abundantly available in the streets and self medicating is not uncommon in UK. 

Another psychedelics researcher, James Rucker from King’s College London, isn’t so sure about Carhart-Harris’ timeline (which I’m not comfortable either), telling The Independent that five years is “possible… but only if everything goes to plan, and you know what they say about best-laid plans.”
So next time when you travel through M1,  look out for majestic magic mushroom fields! 

READ MORE: Magic mushrooms could replace antidepressants within five years, says new psychedelic research centre [The Independent]

Friday 5 April 2019

My Linguistic Relativity thoughts!

I always believed that language helps or drive our thought process. But does an increased vocabulary change the way a person thinks? I'm not entirely sure about it! However it will drive for knowledge, conscious or not, that will leads to a larger vocabulary. A larger vocabulary may facilitate learning - example Nandu, my 10 year old son— he can connect ideas and information better. And knowing (and using) more words can help him communicate those ideas better.

If language can alter one's thought-paths, then certain languages constrain thought to a greater degree than other languages. The reasoning is simple: if our mother-tongue uses abstract terms to define concepts, one must first translate that abstraction to be able to parse it more effectively. This translation is, by its very definition, a constraint.

The native language we speak may determine how your brain solves mathematical puzzles, according to a new study. Brain scans have revealed that Chinese speakers rely more on visual regions than English speakers when comparing numbers and doing sums. Interesting!!  Our mother tongue may influence the way problem-solving circuits in our brains develop, suggest the researchers. But they add that different teaching methods across cultures, or genes, may also have primed the brains of Chinese and English speakers to solve equations differently.

I think most of Indian language, including my mother-tongue  Malayalam, speakers will be having more activity in the visual and spatial brain centre - visuo-premotor association network. The researches suggests that the native English speakers have more activity in the language network known as perisylvian cortices in the left half of the brain. This might be different to the first and second generation 
migrators. I particularly noticed my son's ability of visually thinking about things, but could it be a bit of hereditary 'genes " from us? My wife is pretty good at learning new languages. I speak three languages proficiently but she speaks four. However, I think I'm more of a visual person than my wife :) Unfortunately my  son speaks only 'English' though his parents are multilingual. We still trying to teach him Malayalam, our mother-tongue!

Another thought!

People who suffer some kind of brain damage that stops them using language can still think just fine. It may be that some people think more verbally and others visually; these are really just tools for the thought process;  probably even someone who was blind from birth and then suffered the additional problem of damaging the language centres of their brain, would still be able to think, although it's hard to imagine what that would be like.

Thursday 4 April 2019

Get Rid of Your Negative Feeling!

Do you want to rid yourself of negative thinking, and make it so virtually any circumstance is not only surmountable, but appreciated?
If so, I've got a few tools that can help you make a shift towards optimism in everything you do and experience.
According to the Mayo Clinic, health benefits of positive thinking are plentiful, and include:
  • Longer life span
  • Less depression and overall distress
  • Greater immunity
  • Better cardiovascular health 
  • Better stress coping skills

The theory is that a positive outlook helps a person to cope better, which reduces stress, and also the harmful effects stress has on one's body.
Think about where you may have negativity in your own life: whether in relationships, at work, when times get tough (understandable), or elsewhere. Now, consider how much easier your day to day would be if that negativity was replaced with positivity.

Here's how to get started.

Be Kind to Yourself: Don't say anything to yourself that you wouldn't think was a kind thing to say to someone else. Instead, have compassion with yourself, celebrate your strengths... and go easy on yourself for your weaknesses.
Be Grateful: Instead of focusing on the bad things in your life or what you don't have, focus on what you DO have. I bet you'll find you have plenty in your own life that you should celebrate.Focusing on good things helps you to see the bad things in a better light; you'll be able to better see the balance of positive and negative, and it will lighten your overall worry load.Look Ahead: Instead of focusing on the past, and what "should have been", think about the future and what "could be possible". You can't do anything about the past, but you have a lot of opportunities ahead if you make wise choices in the future.

Wednesday 15 August 2018

Hard and Soft Skills

Have you ever heard come across the terms Hard and Soft skills?

These are 2 different types of skills that we acquire in order to perform and excel in a job, no matter the industry you're in.

Most of us would be familiar with Hard skills as we've been through them since young. In school, we're taught mostly Hard skills. Math, Science, History, Geography - these are all knowledge that can be quantified through the tests and assessments that you have to take. Typically, you'll learn hard skills in the classroom, through books or other training materials, or on the job. Your university degree or vocational training are all Hard skills that have enabled you to land the job you're now in.

However, as I'm sure many of you are that these days, having solid Hard skills doesn't necessarily guarantee you your dream job. Having a degree or two, or having a 4.0 GPA does not mean you'll score the job you've applied for.

And why is this so?

For starters, we're a progressive society. Things are ever changing, and as a result, the way in which we think of solutions to new problems and discoveries have to change constantly. This requires a lot of creative thinking, and flexibility that Hard skills do not always cover. The work culture in many younger companies and start ups these days also focus a lot more on strengths outside of the Hard skills that their employees have. As a result, you may realise that you can no longer succeed on Hard skills alone.

And that's where Soft skills come in!

Soft skills are subjective skills that are much harder to quantify. They're also known as people or interpersonal skills. They relate to the way you interact with other people. Some examples of soft skills include - Communication, Motivation, Problem Solving abilities, Creative Thinking, Time Management and Leadership. It may seem like skills that you naturally learn or know, yet these are skills that are sometimes overlooked. And that is why some people are more successful than others. It's because they're able to leverage on Soft skills to push progress towards their goals or in their jobs. They're able to hone in on their Soft skills to stand out from their peers and co workers.

Sunday 13 May 2018

Public speaking - some simple tips

One thing that I have learned about public speaking, or even just persuasive speaking, which I think falls into psychological.
When talking about something, you need to own your space. You can do this in many ways, but the best way to get people to listen to what you say is to own the space around you. Show confidence, show that you're comfortable. Convince others ‘I am so sure what I'm saying is awesome and true that I am not in the least bit nervous about this speech.’
Walking around is one way to do it. Use up all of the stage. Move. Lean down, stand up, walk to the front, walk to the back. Just be careful not to overdo it, otherwise it might seem more like fidgeting which will have the opposite effect.
Open yourself up. Spread your shoulders, lift your head, widen your stance. Uncrossed legs, relaxed stance, chin up, shoulders back. This is how you want to look.
Another small tip is to achieve the ‘I know what I'm talking about’ effect is to bring a drink with you. It shows you're calm, allows you to take a little rest, pauses show that you're thinking about what you're saying. Depending on the drink, it can also show confidence in of itself. I always take a crystal glass with me wherever I go and fill it with just spring water. Never use a bottle or a plastic/paper cup. A clear crystal glass projects a good professional outlook.

Sunday 5 November 2017

Intrusive thoughts and Mind Control

Intrusive Thoughts Might Be Caused By a Shortage of a Certain Chemical

Scientists have linked a neurotransmitter known as GABA to unwanted and intrusive thoughts. These findings could have a major impact on our understanding of conditions like obsessive-compulsive disorder, post-traumatic stress disorder, and schizophrenia

Most of us know the feeling of being unable to distract ourselves from a particular thought, however much we might want to. Now, scientists might have found the reason why.

In a study carried out at the University of Cambridge, participants were given pairs of words to associate with one another. The words were unrelated in order to ensure that pre-existing associations didn’t have any influence. Participants were then given a word and either a green or a red signal. If it was the former, they would try to recall the other half of the pairing, and if it was the latter, they would try to deliberately suppress the associated term from their mind.

While this test was being carried out, participants’ brains were monitored using functional magnetic resonance imaging, a technique that monitors changes in blood flow, as well as magnetic resonance spectroscopy, which tracks chemical changes.

Participants with the highest concentrations of a chemical known as Gaba in their hippocampus were best at suppressing the unwanted thoughts. Gaba is the brain’s primary inhibiting neurotransmitter, stifling the activities of other cells when it’s released.

“What’s exciting about this is that now we’re getting very specific,” said Professor Michael Anderson, who led the study, in an interview with the BBC. “Before, we could only say ‘this part of the brain acts on that part’, but now we can say which neurotransmitters are likely to be important.”

A difficulty with or an inability to break free from intrusive and unwanted thoughts are a reality both for neurotypical people and also for those with various types of mental illness. Conditions ranging from obsessive-compulsive disorder and post-traumatic stress disorder to depression and schizophrenia all count this type of behaviour among their symptoms.

As such, there are hopes that these findings could offer further insight into the chemical basis of these disorders. At present, much of the research into treatment methods has centered around helping the prefrontal cortex to function normally. However, Anderson believes that figuring out a way to promote Gaba activity in the hippocampus could actually offer more positive results.

Wednesday 7 June 2017

Some interesting Life Hacks!

Dear some Life Hacks for you all!
One of the tricks to catch someone telling a lie is to see if they repeatedly look to their left while talking to you or do not make any eye contact.
Although it is tough but if you can get into the habit of not only remembering someone’s name when you first meet them, but using their name in the subsequent conversation you have, they’ll find you terribly charming and wonderful.
To appear more confident, self-assured, thoughtful and knowledgeable - avoid using many filler words like 'uh' 'umm' 'err' etc. Instead, use the silence (not too long) to order your thoughts and more coherently communicate whatever it is you are trying to get across.
People perceive other people with better posture as more important and confident people.
During negotiations, use silence as a weapon. Most people are uncomfortable with it an they will try to break it by giving up a key point.
If you ask someone a question and they only partially answer, give them a few seconds. By remaining silent and keeping your eye contact, they will usually continue talking.
You can restore your attention by taking a sneak peek of even just 40 seconds of nature. A 2015 Australian study found that looking at a flowering and grassy rooftop helped participants make less mistakes as compared to those staring at a concrete building. The lead author of the study says that even looking at an image of nature can help improve work performance.
Instead of looking for a less populated pathway right in front of you, look in the direction you want to go and point yourself that way. People will instinctively get out of your way, as they tend to watch others' eyes and body language to determine their direction.
Last but not the least,

Happiness is Contagious: 

It's not exactly Ebola, but happiness is contagious. And the effect is impressive - happiness can strengthen your immune system,decreases pain and chronic diseases and provide stress relief. One study even found that happiness can lower your risk of heart disease. Yet another reason to ditch the negative jerks in your life and stay positive. Laugh, and the whole world laughs with you!

Sunday 15 January 2017

What is the first impression means.....!

A Harvard psychologist says people judge you based on 2 criteria when they first meet you!
People size you up in seconds, but what exactly are they evaluating?
Harvard Business School professor Amy Cuddy has been studying first impressions alongside fellow psychologists Susan Fiske and Peter Glick for more than 15 years, and has discovered patterns in these interactions.
In her new book, "Presence," Cuddy says that people quickly answer two questions when they first meet you:
Can I trust this person?
Can I respect this person?
Psychologists refer to these dimensions as warmth and competence, respectively, and ideally you want to be perceived as having both.
Interestingly, Cuddy says that most people, especially in a professional context, believe that competence is the more important factor. After all, they want to prove that they are smart and talented enough to handle your business.
But in fact, warmth, or trustworthiness, is the most important factor in how people evaluate you.
"From an evolutionary perspective," Cuddy says, "it is more crucial to our survival to know whether a person deserves our trust."
It makes sense when you consider that in cavemen days it was more important to figure out if your fellow man was going to kill you and steal all your possessions than if he was competent enough to build a good fire.
But while competence is highly valued, Cuddy says that it is evaluated only after trust is established.And focusing too much on displaying your strength can backfire.
She says that MBA interns are often so concerned about coming across as smart and competent that it can lead them to skip social events, not ask for help, and generally come off as unapproachable.
These overachievers are in for a rude awakening when they don't get a job offer because nobody got to know and trust them as people.
Cuddy says:
If someone you're trying to influence doesn't trust you, you're not going to get very far; in fact, you might even elicit suspicion because you come across as manipulative. A warm, trustworthy person who is also strong elicits admiration, but only after you've established trust does your strength become a gift rather than a threat.

Tuesday 1 November 2016

The 36 Questions That Lead to Love

1. Given the choice of anyone in the world, whom would you want as a dinner guest?
2. Would you like to be famous? In what way?
3. Before making a phone call, do you ever rehearse what you're going to say? Why?
4. What would constitute a perfect day for you?
5. When did you last sing to yourself? To someone else?
6. If you were able to live to the age of 90 and retain either the mind or body of a 30-year old for the last 60 years of your life, which would you choose?
7. Do you have a secret hunch about how you will die?
8. Name three things you and your partner appear to have in common.
9. For what in your life do you feel most grateful?
10. If you could change anything about the way you were raised, what would it be?
11. Take four minutes and tell you partner your life story in as much detail as possible.
12. If you could wake up tomorrow having gained one quality or ability, what would it be?
13. If a crystal ball could tell you the truth about yourself, your life, the future or anything else, what would you want to know?
14. Is there something that you've dreamt of doing for a long time? Why haven't you done it?
15. What is the greatest accomplishment of your life?
16. What do you value most in a friendship?
17. What is your most treasured memory?
18. What is your most terrible memory?
19. If you knew that in one year you would die suddenly, would you change anything about the way you are now living? Why?
20. What does friendship mean to you?
21. What roles do love and affection play in your life?
22. Alternate sharing something you consider a positive characteristic of your partner. Share a total of five items.
23. How close and warm is your family? Do you feel your childhood was happier than most other people's?
24. How do you feel about your relationship with your mother?
25. Make three true "we" statements each. For instance, "we are both in this room feeling..."
26. Complete this sentence "I wish I had someone with whom I could share..."
27. If you were going to become a close friend with your partner, please share what would be important for him or her to know.
28. Tell your partner what you like about them: be honest this time, saying things that you might not say to someone you've just met.
29. Share with your partner an embarrassing moment in your life.
30. When did you last cry in front of another person? By yourself?
31. Tell your partner something that you like about them already.
32. What, if anything, is too serious to be joked about?
33. If you were to die this evening with no opportunity to communicate with anyone, what would you most regret not having told someone? Why haven't you told them yet?
34. Your house, containing everything you own, catches fire. After saving your loved ones and pets, you have time to safely make a final dash to save any one item. What would it be? Why?
35. Of all the people in your family, whose death would you find most disturbing? Why?
36. Share a personal problem and ask your partner's advice on how he or she might handle it. Also, ask your partner to reflect back to you how you seem to be feeling about the problem you have chosen.

Sunday 7 February 2016

How do I become mentally stronger?

Here’s very simple 6 top tips for you:
1. Eat the elephant.
How do you eat an elephant? One bite at a time. Take insurmountable goals and break them down into smaller objectives.
2. Use visualisation.
Run vivid scenarios of yourself succeeding over and over inside your heads. This maximizes the chance of success when the time comes.
3. Practice emotional control.
Use breathing techniques such as the “4 by 4 for 4” (4 seconds in, 4 seconds out for 4 minutes) to keep your stress levels under control.
4.Use self talk.
Reframe external events in a positive light. Understand that it is not the EVENT but their INTERPRETATION that matters.
5. Celebrate small victories.
See the beauty of small victories in tough times. This keeps morale high so they can keep fighting the good fight.
6. Value your tribe.
Care for their team. Lose the tribe and you lose everything.
The techniques are important, but actually executing them is even more so. ๐Ÿ’ฏ๐Ÿ”

Wednesday 10 April 2013



Max Velmans, Goldsmiths, University of London, New Cross, London SE14 6NW; email;
Journal of Consciousness Studies, 16(5), 2009, pp 139-156

Abstract. Definitions of consciousness need to be sufficiently broad to include all examples of
conscious states and sufficiently narrow to exclude entities, events and processes that are
not conscious. Unfortunately, deviations from these simple principles are common in
modern consciousness studies, with consequent confusion and internal division in the field.
The present paper gives example of ways in which definitions of consciousness can be either
too broad or too narrow. It also discusses some of the main ways in which pre-existing
theoretical commitments (about the nature of consciousness, mind and world) have intruded
into definitions. Similar problems can arise in the way a “conscious process” is defined,
potentially obscuring the way that conscious phenomenology actually relates to its neural
correlates and antecedent causes in the brain, body and external world. Once a definition of
“consciousness” is firmly grounded in its phenomenology, investigations of its ontology and
its relationships to entities, events and processes that are not conscious can begin, and this
may in time transmute the meaning (or sense) of the term. As our scientific understanding of
these relationships deepen, our understanding of what consciousness is will also deepen. A
similar transmutation of meaning (with growth of knowledge) occurs with basic terms in
physics such as "energy", and "time."

Why is it difficult to define consciousness?

As George Miller wrote in 1962, "Consciousness is a word worn smooth by a million tongues."
Almost 50 years later, little has changed. The term means many different things to many
different people, and no universally agreed "core meaning" exists. This is odd, as we each have
"psychological data" about what it is like to be conscious or to have consciousness to serve as
the basis for an agreed definition.

This uncertainty about how to define consciousness is partly brought about by the way global
theories about consciousness (or even about the nature of the universe) have intruded into
definitions. In classical Indian writings such as the Upanishads, consciousness is thought to be
the essence of ฤ€tman, a primal, immanent self that is ultimately identified with Brฤhman—a
pure,transcendental, subject-object-less consciousness that underlies and provides the ground
of being of both Man and Nature (Sen, 2008). In the classical Western tradition, "substance
dualists" such as Plato and Descartes bifurcated the universe, believing it to consist of two
fundamental kinds of stuff, material stuff and the stuff of consciousness (a substance
associated with soul or spirit). Following the success of the brain sciences and related sciences,
20th Century theories of mind in the West became increasingly materialistic, assuming physical
“stuff” to be basic, and consciousness in some way “supervenient” or dependent on the
existence of physical forms. For example, "property dualists" such as Sperry (1969) took
consciousness to be a special kind of property that is itself non-physical, but which emerges
from physical systems such as the brain once they attain a certain level of complexity. Taking
materialism to its logical conclusion, "reductionists" such as Crick (1994) and Dennett (1991)
argued consciousness to be nothing more than a state or function of the brain. Within
cognitive psychology, there were many similar reductive proposals which identified
consciousness with some aspect of human information processing, for example with working
memory, focal attention, a central executive, or a “global workspace”(e.g. Baars, 1988).
It should be apparent that these wide-ranging disparities arise more from pre-existing
theoretical commitments (about the nature of consciousness, mind and world) than from the
everyday phenomenology of consciousness itself. In the modern literature, for example,
Dennett provides a prominent example of the triumph of materialist theory over
phenomenological evidence when he tried to deny the very existence of phenomenal qualities
(as normally understood). He made this perfectly clear when he writes: "Philosophers have adopted various names for the things in the beholder (or properties of the beholder) that have been supposed to provide a safe home for the colours and the rest of the properties that have been banished from the external world by the triumphs of physics:raw feels, phenomenal qualities, intrinsic properties of conscious experiences, the qualitative content of mental states, and, of course, qualia, the term I use.

There are subtle differences in how these terms have been defined, but I am going to ride roughshod over them. I deny that there are any such properties. But I agree wholeheartedly that there seem
to be." (Dennett, 1991, p372 - my italics)

Dennett arrives at this view by presupposing that information about brain and behaviour
obtained from a third-person perspective is scientific and reliable, while first-person data about
conscious experience tells us nothing about its ontology at all.1
European phenomenology and classical Indian philosophy assume the opposite to be true. Accordingly, their investigations of consciousness have been primarily phenomenological.2 Within modern consciousness studies there are also many intermediate theoretical positions with associated research paradigms that take both the existence of the material world and the existence of
I have given a detailed critique of this aspect of Dennett’s position that I do not have space to repeat here (see Velmans, 2001, 2007a, 2009 chapter 5); see also Zahavi (2007), Beenfeldt (2008).
See Gallagher, 2007, Zahavi, 2007 for recent reviews of European phenomenological approaches.
Note however that classical Indian conclusions about the nature of consciousness arise largely from altered conscious states consequent on prolonged periods of meditation, and this can be an additional source of confusion when comparing Eastern and Western understanding of everyday conscious phenomenology. The pure, contentless consciousness said to be experienced in such states is, in various writings, thought to underly all of Nature, which makes this a claim about what in the West is sometimes referred to as “the ground of being” or, in Kantian terms, “the thing in itself,” rather than a claim about the forms of “phenomenal consciousness,” that are more usually investigated in modern consciousness studies. consciousness seriously, for example viewing first- and third-person investigations of the mind/brain as complementary sources of information about its nature.

It should come as no surprise that such diverse assumptions about the nature of consciousness and howwe can study it have created divisions between research communities that can be difficult to cross. There can, for example, be no point of convergence and certainly no consensus between
researchers who take the existence of conscious phenomenology to be both self-evident and
ontologically primary, with those who give no credence to that phenomenology at all.

Given this diversity, some consciousness researchers have doubted that a systematic study
of “consciousness” as such, is even possible. Sloman (1991) for example argued that "people who
discuss consciousness delude themselves in thinking that they know what they are talking's
not just one thing but many things muddled together"—rather like our "multifarious uses of ‘energy’
(intellectual energy, music with energy, high energy explosion, etc.)", and Stanovich (1991) complained that "the term "consciousness" fractionates into half a dozen or more different usages." For him, “consciousness” is a "botched concept"; a psychiatric institution is too good for it—and it deserves the "death penalty." Given this, they suggest that one can make no generalisations about it.
The obvious counterargument is that there is nothing to prevent discussion and organised research into aspects of “consciousness” denoted by a given, specific usage of that term. The multiple uses of the term “energy” in natural language have not in any way impeded a systematic study of energy in physics.

Similarly, the flourishing of consciousness studies over the last 20 years has made it clear that, despite its diverse referents in natural language, a systematic study of “consciousness” is both possible and actual. For research to proceed, all one needs is a sufficiently well-specified use of the term for a
community of researchers to agree that they are investigating the same thing.

To what does the term "consciousness" refer?

But where should we begin? As with any term that refers to something that one can observe
or experience it is useful, if possible, to begin with an ostensive definition, i.e. to "point to" or
"pick out" the phenomena to which the term refers and, by implication, what is excluded.
Normally we point to some thing that we observe or experience. The term “consciousness”
however refers to experience itself. Rather than being exemplified by a particular thing that we
observe or experience, it is exemplified by all the things that we observe or experience.
Something happens when we are conscious that does not happen when we are not
conscious—and something happens when we are conscious of something that does not
happen when we are not conscious of that thing. We know what it is like to be conscious when
we are awake as opposed to not being conscious when in dreamless sleep. We also know what
it is like to be conscious of something (when awake or dreaming) as opposed to not being
conscious of that thing.

This everyday understanding of consciousness based on the presence or absence of
experienced phenomena provides a simple place to start. A person, or other entity, is
conscious if they experience something; conversely, if a person or entity experiences nothing
(See Velmans 1991b, 2007b for introductions to this form of “psychological complementarity”, and readings in Varela & Shear ( 1999), Velmans (2000), Jack & Roepstorff (2003, 2004) they are not conscious. Elaborating slightly, we can say that when consciousness is present, phenomenal content (consciousness of something) is present. Conversely, when phenomenal content is absent, consciousness is absent. This stays very close to everyday usage and it provides a simple place of departure on which widely diverging theories can agree.It also makes sense to stay as close as possible to everyday, natural language usage for related terms. In common usage, the term
"consciousness" is often synonymous with "awareness", "conscious awareness", and
“experience”. For example, It makes no difference in most contexts to claim that I am
"conscious of" what I think, "aware of" what I think, "consciously aware" of what I think, or
that I can “experience” what I think. Consequently, to minimise confusion, it is important not
to load these terms with added meanings that are peculiar to a given theoretical position.6
This applies equally to the “contents of consciousness”. The "contents of consciousness"
encompass all the phenomena that we are conscious of, aware of, or experience. These
include not only experiences that we commonly associate with ourselves, such as thoughts,
feelings, images, dreams, body sensations and so on, but also the experienced three dimensional world (the phenomenal world) beyond the body surface.

Some important distinctions

However some terminological distinctions are important. In some older writings, for example
in the work of Descartes, "consciousness" is not clearly differentiated from "mind." Given the
extensive, current evidence for preconscious and unconscious mental processing, this usage is too broad. How phenomenal consciousness relates to preconscious and unconscious mental
processing is now a major topic for psychological research. To avoid confusion, and to enable
such research, it is important to reserve the term "mind" for psychological states and processes
that may or may not be "conscious".

Descartes also famously believed thought to epitomise the nature of consciousness, and
consequently defined it as a “substance that thinks” (res cogitans), which distinguishes it (in his
view) from material substance that has extension in space (res extensa). Modern psychology
accepts that verbal thoughts (in the form of phonemic imagery or ‘inner speech’) are amongst
It is worth noting that Eastern philosophies refer to a state of "pure consciousness," without any phenomenal contents (Shear & Jevning, 1999, Shear, 2007), although many characterisations are nevertheless offered of this state, such as sat-chit-ananda (being-consciousness-bliss) in Hindu thought, or sunyata (emptiness) in Mahayana Buddhism (Fontana, 2007). As these possibilities do not have a direct bearing on the problems of defining consciousness within the Western discourse, we can safely leave them to one side for now, without dismissing them.

Even eliminative/reductive theories such as Dennett’s agree that that conscious phenomenology seems to exist, and this provides the point of departure for their attempts at phenomenal elimination/ reduction. For example in some theories "awareness" is thought of as a form of low-level consciousness that is distinct from full consciousness. This is not a serious problem for the present proposal, provided that the situation described has some phenomenal content (for example where one is dimly aware of a stimulus). However serious confusions can arise in situations where the term "awareness" is applied to situations where there is no relevant phenomenal content, for example, when "awareness" refers to preconscious information processing, or worse, to the non-conscious information processing which accompanies consciousness (as proposed by Chalmers, 1995). In the present usage, being "aware of" non-conscious information processing is a contradiction in terms. (See, for example, Dixon (1981), Kihlstrom (1987), Velmans (1991b), Reber (1993), Wilson (2002), Goodale & Milner (2004), Jeannerod (2007), Kihlstrom, Dorfman & Park (2007), Merikle (2007)
the contents of consciousness. However it does not accept that thoughts exemplify all conscious contents. Unlike thoughts, pains, tactile sensations, itches and other body experiences appear to have both spatial location and extension in different regions of the body, and the sights and sounds of the experienced external world (the phenomenal world) appear to have locations and extensions in a surrounding three-dimensional space.

These interoceptive and exteroceptive experiences also differ widely from each other and many
descriptive systems have been developed for investigating their phenomenology (in studies of
visual and auditory perception, emotion, pain, and so on). It should be evident that such
developments in phenomenology are an essential first step in characterising what it is about
consciousness that needs to be explained—and that restricting the phenomenology of
“consciousness” to the phenomenology of “thought” is too narrow.

In other, more modern writings, "consciousness" is sometimes taken to be synonymous with
"self-consciousness". As one can be conscious of many things other than oneself (other people,
the external world, etc.), this usage is also too narrow. To allow a clear distinction between
consciousness of oneself and consciousness of things other than oneself, it makes more sense
to reserve the term “self-consciousness” for a special form of reflexive consciousness in which
the object of consciousness is the self or some aspect of the self.

The term "consciousness" is also commonly used to refer to a state of wakefulness. Being
awake or asleep or in some other state such as coma clearly influences what one can be conscious of. However these global states have a complex relationship to phenomenal consciousness. When sleeping, for example, one can still have visual and auditory experiences in the form of dreams. Conversely, when awake there are many things at any given moment that one does not experience. So in a variety of contexts it is necessary to distinguish "consciousness" in the sense of "phenomenal consciousness" from wakefulness and other states of arousal, such as dream sleep, deep sleep, and coma. Finally, "consciousness" is sometimes used to mean "knowledge", in the sense that if one is conscious of something one also has knowledge of it. This is an important feature of consciousness (that I do not have space to examine here).

However, at any moment, much knowledge is unconscious, or implicit (for example, the knowledge gained over a lifetime, stored in long-term memory). So consciousness and knowledge cannot be co-extensive.

It is widely accepted that many experienced phenomena have apparent location. Whether there is also a sense in which such phenomena also have a real spatial location and extension (in the phenomenal body and external world outside the brain) is a fundamental, contested issue within current consciousness studies that goes beyond the scope of the present paper. Detailed evaluations of the competing arguments are given in Velmans (2008, 2009 chapter 7).

It remains useful to distinguish the various global conditions for the existence of consciousness (for example the differences between being awake, in dream sleep, dreamless sleep, and deep coma) from the added conditions which determine its varied phenomenal contents (for example having visual rather than auditory experiences). However, for the purposes of finding an agreed, core definition of phenomenal consciousness from which investigations can proceed, it makes sense to retain the convention that unless one is conscious of something one is not conscious. Conversely if one is conscious of something (e.g. while dreaming) one is conscious.

Phenomenal consciousness enables a special kind of knowledge: To be conscious of something is to know it in a way that makes itsubjectively real. Bertrand Russell called this “knowledge by acquaintance”, which he contrasted with the more abstract “knowledge by description” provided by verbal descriptions. This important, first-person function of phenomenal consciousness and its relation to the many proposed, third-person functions of consciousness is discussed in detail in Velmans (2009 chapters 12, 13, and 14).

The above, broad definitions and distinctions have been quite widely accepted in the
contemporary scientific literature (see, for example, Farthing, 1992; readings in Velmans, 1996,
Velmans & Schneider, 2007)—although by no means universally, as we will see below. Agreeing on definitions is important. Once a given reference for the term "consciousness" is fixed in its phenomenology, the investigation of its nature can begin.

How not to define consciousness

As noted above, reductionists and non-reductionists adopt fundamentally differing
assumptions about the ontology of consciousness and there are many instances where these
differing assumptions about ontology have intruded into how phenomenal consciousness
has been defined. It is common for example for reductive physicalists and functionalists to
take it for granted that an advanced form of brain science will ultimately demonstrate
phenomenal consciousness to be nothing more than a state or function of the brain. If so,
nothing would be lost by defining it in that way. However most theories of consciousness
that resist a reduction of conscious phenomenology to brain states and/or functions fully
accept that there is an intimate relationship between consciousness and brain. What is at
stake is the nature of this intimate relationship. For example, physicalist, functionalist,
naturalistic dualist and modern dual-aspect theories agree that, in humans, every distinct
conscious experience is likely to be accompanied by distinct, correlated conditions in the brain
(the neural correlates of consciousness or NCC), but naturalistic dualist, and dual-aspect
theories resist the reduction of phenomenal consciousness to brain states. Dual-aspect theory
for example suggests that conscious experiences and their correlated brain states are how the
mind appears when viewed from respectively first- and third-person perspectives, and that
these aspects of mind are complementary and mutually irreducible (see e.g. Velmans, 1991b,
2009 chapter 13).

If so, the discovery of the neural correlates of given experiences will not settle the fundamental differences amongst these theories. Nor would the discovery of antecedent neural causes settle these differences. To achieve a genuine reduction, conscious experiences would have to be shown to be ontologically identical to their neural causes and/or correlates. Discovery of the neural causes and or correlates would not achieve this for the simple reason that causation, correlation and ontological identity are fundamentally different relationships.

In short, no ontological view is automatically privileged by the likely advance of science, and,
given the far-reaching consequences of reductionism and its alternatives it is important not to
define phenomenal consciousness in a way that presupposes the outcome of this debate, or
finesses it in favour of one outcome or another. Unfortunately, this practice is widespread
both in common culture13 and in the scientific and philosophical literature. Dennett, Searle,
Chalmers (1996) provides a naturalistic dualist analysis of how conscious experiences relate to brain states that is similarly non-reductionist.

If A is identical to B, then B is identical to A (symmetry) and all the properties of A and B must be identical (Leibniz’s law). If A correlates with B, then B correlates with A (symmetry), but it does not follow that all the properties of A and B must be identical (correlation need not obey Leibniz’s law). If A causes B, it neither follows that B causes A, nor that the properties of A and B are identical (neither symmetry, nor Leibniz’s law)— for a fuller discussion see Velmans (1998, 2002, 2009 chapter 3). For example newspaper reports of PET or fMRI scans producing ‘pictures of conscious thoughts’, emotions etc. in the brain are ubiquitous, completely oblivious of the fact that these are actually indirect measures of activities that correlate with the experiences in question rather than pictures of the experiences themselves,

Block, and Baars provide a few prominent examples (amongst many). As noted above,
Dennett simply declares first-person access to phenomenal qualities to have no place in
third-person science, and, therefore, no ultimate place in an understanding of consciousness at all! Searle (2007), by contrast, fully accepts that conscious states have special phenomenal properties, for example that they are intentional (about something), subjective, and private (viewable only from a first-person perspective)—all characteristics that traditionally distinguish the mental from the physical. However he then simply declares such facts about consciousness to be ‘objective physical facts’ about the brain, thereby reducing the domain of the “mental” to a subclass of what is “physical” by an act of redefinition—but leaving the problem of how objects such as brains could produce such intentional, subjective, private states untouched. Block (1995) also entirely accepts the
existence of phenomenal consciousness (with its special properties). However, he argues
that there is another kind of consciousness, which he terms “access consciousness” that
enables “information access” in the central nervous system, thereby giving consciousness a
major role to play in the brain’s activities. While this avoids reducing phenomenal
consciousness to a function of the brain, this redefinition of information access as “access
consciousness” risks inflating a brain function to a conscious status that it does not possess.

Information access and information availability have been widely recognised aspects of
human information processing since the advent of cognitive psychology in the 1960’s, and it
is true that information which enters phenomenal consciousness can be accessed,
rehearsed, entered into long-term memory, used for the guidance of action and so on.
However, the processes that actually enable information access, rehearsal, transfer to longterm memory and guidance of action are not themselves conscious (if they were there would be no need to subject such processes to detailed investigation within cognitive psychological research—see Velmans, 1991a). In short, “access consciousness” is not actually a form of consciousness. The conscious part of “access consciousness” is just phenomenal consciousness, and the processes that enable access to items in phenomenal consciousness are not conscious at all.

How to define a “conscious process”

For the purposes of definition, the importance of retaining an initial, clear distinction between
information processing and the conscious experiences that may or may not accompany it becomes
evident as soon as one reflects on the very different ways that the term “conscious process” has
been used in the literature. In Velmans (1991a) I have argued that the psychological and
philosophical literature confounds three distinct senses in which a process might be said to be
“conscious.” It might be conscious:
(a) in the sense that one is conscious of the process
(b) in the sense that the operation of the process is accompanied by consciousness (of its
results) and and completely oblivious of the fact that the phenomenology of a subject’s experiences cannot be viewed from a third-person perspective (the classical philosophical problem of “other minds”).
(c) in the sense that consciousness enters into or causally influencesthe process.

We do not have introspective access to how the preconscious cognitive processes that enable
thinking produce individual, conscious thoughts in the form of “inner speech.” However, the
content of such thoughts and the sequence in which they appear does give some insight into
the way the cognitive processes (of which they are manifestations) operate over time in
problem solving, thinking, planning and so on. Consequently such cognitive processes are
partly conscious in sense (a), but only in so far as their detailed operation is made explicit in
conscious thoughts, thereby becoming accessible to introspection.

Many psychological processes are conscious in sense (b), but not in sense (a)—that is, we are
not conscious of how the processes operate, but we are conscious of their results. This applies
to perception in all sense modalities. When consciously reading this sentence for example you
become aware of the printed text on the page, accompanied, perhaps, by inner speech
(phonemic imagery) and a feeling of understanding (or not), but you have no introspective
access to the processes which enable you to read. Nor does one have introspective access to
the details of most other forms of cognitive functioning, for example to the detailed operations
which enable “conscious” learning, remembering, engaging in conversations with others and so

Crucially, having an experience that gives some introspective access to a given process, or
having the results of that process manifest in an experience, says nothing about whether that
experience carries out that process. That is, whether a process is “conscious” in sense (a) or (b)
needs to distinguished from whether it is conscious in sense (c). Indeed, it is not easy to
envisage how the experience that makes a process conscious in sense (a) or (b) could make it
conscious in sense (c). Consciousness of a physical process does not make consciousness
responsible for the operation of that process (watching a kettle does not determine when it
comes to the boil). So, how could consciousness of a mental process carry out the functions of
that process? Alternatively, if conscious experience results from a mental process it arrives too
late to carry out the functions of that process.

How not to define a “conscious process”

It is nevertheless common for theorists to contrast human information processing that is either
accompanied or not accompanied by a conscious experience, and then attribute any functional
differences in processing to the activities of consciousness. Indeed Baars & McGovern (1996)
explicitly advocate this method (which they call “contrastive analysis”) for determining the
functions of consciousness. As they point out, the brain has hundreds of different types of
unconscious specialised processors such as feature detectors for colours, line orientation and
faces, which can act independently or in coalition with one another, thereby bypassing the
limited capacity of consciousness. These processors are extremely efficient, but restricted to
their dedicated tasks. The processors can also receive global messages and transmit them by
‘posting’ messages to a limited-capacity, global workspace whose architecture enables systemwide integration and dissemination of such information. Such communications allow new links
to be formed between the processors, and the formation of novel expert ‘coalitions’ able to
work on new or difficult problems. Once processes enter the global workspace they ‘become
conscious’, and Baars & McGovern assume the functions of the global workspace to be the
functions of consciousness. Within their model, the global workspace is essential for
organising novel, complex activities. Given this, it is not surprising that they find many things
for phenomenal consciousness to do. For example:

  1. By relating input to its context, consciousness defines input, removing its ambiguities in perception and understanding.
  2. Consciousness is required for successful problem solving and learning, particularly where novelty is involved.
  3. Making an event conscious raises its “access priority,” increasing the chances of successful adaptation to that event.
  4. Conscious goals can recruit subgoals and motor systems to carry out voluntary acts.
  5. Making choices conscious helps to recruit knowledge resources essential to arriving at an appropriate decision.
  6. Conscious inner speech and imagery allow us to reflect on and, to an extent, control our conscious and unconscious functioning.
  7. In facing unpredictable conditions, consciousness is indispensable in allowing flexible responses.

“In sum, consciousness appears to be the major way in which the central nervous system
adapts to novel, challenging and informative events in the world” (Baars & McGovern, 1996,

Global workspace theory provides one of the best, current models of brain functions closely
associated with consciousness. Given this, why should an identification of consciousness with
the operations of the global workspace present a problem? For Baars, a third-person account
of consciousness in terms of information in a global workspace is an account of subjective
experience—that is, it is an account of consciousness as such (Baars, 1994, 2007). But the
difficulties of incorporating first-person, phenomenal consciousness within a third-person
account of information processing in this way are well illustrated by Baars’ many different
attempts to grapple with this issue:

In his earlier writings, Baars (1991) equated consciousness with focal attention, arguing that
they “covary so perfectly, we routinely infer in our everyday life that they reflect a single
underlying reality.” Later, however, Baars (1997a) modified his position to viewing attention as
the “gatekeeper” for the global workspace and therefore the gatekeeper to consciousness.
Thus, “attention creates access to consciousness”, but “consciousness is needed to create
access to unconscious processing resources”, and “... we can create access to any part of the
brain using consciousness.” (Baars, 1997b, p296; see also Baars et al, 1997) In short,
consciousness is now thought to carry out the many functions which require global access to
unconscious processing resources such as system-wide integration and dissemination of
information, the formation of new links between unconscious processors, and so on (and this
remains his position, as noted above). Unfortunately, in his summary of his 1997b position,
Baars once again shifts his position (to one different to that outlined in the body of his paper)
now stressing that, “In the view presented here, global access may be a necessary condition for consciousness; but in the nature of science we simply do not know at this time what would be the truly sufficient conditions.” (p308)

If global access is a necessary (but not sufficient) condition for consciousness, then global
access is causally antecedent to consciousness. However, if consciousness creates global
access, then consciousness is causally antecedent to global access. Baars tries to have it both
ways. Nor does he consider the three ways in which a process can be said to ‘be conscious’,
with their very different consequences for the functions of consciousness. Such confusions
illustrate the need to analyse the precise relation of conscious phenomenology to its
associated information processing with care. Phenomenal consciousness in humans is
unquestionably related to certain forms of information processing in humans. However
reductive redefinitions of consciousness in terms of the processing with which it is associated
impedes a clear analysis of how phenomenal consciousness actually relates to its associated
processing, thereby obscuring rather than clarifying its role in the economy of mind.


There is far more to be said about consciousness and its characteristics (see e.g. Velmans,
2009). However this brief, introductory paper is intended merely to deal with some
preliminary issues regarding how to approach and how not to approach its definition.
Hopefully, the above makes it clear that consciousness understood as phenomenal
consciousness provides a secure departure point for scientific and philosophical
investigations of its nature. Conversely, theories of consciousness that do not in some way
deal with its phenomenology are not theories of consciousness.

Maybe consciousness will ultimately be shown to be nothing more than a state or function
of the brain—and maybe it won’t. That is, after all, what much of the current debate is
about. But it is a mistake to define consciousness in a way that begs this question. It is a
mistake to claim that one is investigating phenomenal consciousness directly when one is
investigating its neural causes and correlates. And it is similarly a mistake to presume
phenomenal consciousness to be identical to the operations of some aspect of information
processing with which it is associated, for example the operations of a “global workspace.”
The mistake in these instances is one of premature closure. If one makes up one’s mind
about the ontology of phenomenal consciousness before fully investigating how its
phenomenology relates to processing in the brain and surrounding world, one precludes a
deeper understanding of that ontology. Conversely, no research is impeded by remaining
open.One can for example investigate the neural causal antecedents and correlates of given
conscious states whether one is a physicalist, a naturalistic dualist or a dual-aspect theorist.
Once a given reference for the term "consciousness" is fixed in its phenomenology, the
investigation of its nature can begin, and this may in time transmute the meaning (or sense) of
the term. As Dewey (1910) noted, to grasp the meaning of a thing, an event or situation is to
see it in its relations to other things—to note how it operates or functions, what consequences
follow from it, what causes it, and what uses it can be put to. Thus, to understand what
consciousness is, we need to understand what causes it, what its function(s) may be, how it
relates to non-conscious processing in the brain, and so on. As our scientific understanding of
these matters deepens, our understanding of what consciousness is will also deepen. A similar
transmutation of meaning (with growth of knowledge) occurs with basic terms in physics such
as "energy", and "time."


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