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Page 1: 1 Available for download from: www. bernardbaars.pbwiki.com Bernard J. Baars The Neurosciences Institute San Diego  Conscious experiences.

1 Available for download from: www. bernardbaars.pbwiki.com

Bernard J. Baars

The Neurosciences InstituteSan Diego www.nsi.edu/users/baars

Conscious experiences trigger

widespread adaptive changes in the human brain:

The case of conscious neurofeedback.

Train movie -

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How can scientists study consciousness?

“The study… of the distribution of consciousness shows it to be exactly such as we might expect in an organ added for the sake of steering a nervous system grown too complex to regulate itself.”

--- William James, The Principles of Psychology, 1890, p. 141

That is, we need to study contrastive cases… allowing experimental comparisons between closely matched conscious and unconscious conditions.

Wiliam James (1842-1910)

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As William James recommended, we compare similar conscious and unconscious conditions --- it's "the distribution of consciousness" that can reveal its functions.

(Rees, Koch & Kreiman, 200x)

Binocular rivalry permits close comparisons between conscious vs. unconscious input streams

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Global Workspace Theory.

Conscious experiences evoke brain-wide distribution

of focal (conscious) contents.

Evidence from:

fMRI (Dehaene, Rees, etc),

Episodic learningMTL-neocortex'

NN Models & large-scale simulations; EEG evoked potentials (Revonsuo, Dehaene),

Waking vs. unconscious EEG;

… and

THE VERY WIDE REACH OF conscious

NEUROFEEDBACK.

Global broadcasting of conscious visual contents

Visual cortex

Visual cortex

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A remarkable range of conscious N-feedback phenomena.

(neurofeedback = brain-based biofeedback; Baars, 1988, etc.) (PubMed refs: about 7,000).

GWT suggested that conscious feedback from the brain-triggered display is broadcast globally, so that motor networks can act locally to plan and trigger voluntary actions --- unless they encounter inhibition.

(Technically: "local processing initiative in a highly distributed society of

parallel processors"; Baars, 1988)

Feedback must be conscious --- almost everything else is not.

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A very large range of brain activities are modifiable by conscious N-Feedback.

(Baars, 1988, etc) In animals --- learned, voluntary control of almost any arbitrary SINGLE NEURON, or almost any arbitrary POPULATION of neurons has been reliablr reported for about fifty years. [misleadingly called "Operant conditioning"]

In humans, control of alpha EEG. EMG & nl autonomic functions has been long known.

Newer findings: conscious neurofeedback learning has been reported for:

1. EEG --- almost any brain rhythm, frequency band or scalp location, singly or combined. Alpha-gamma coupling, synchrony, desynchrony, etc.

2. Brain rhythms associated with specific brain functions, like memory recall, executive functions, sleep and motor control.

3. Normative EEG patterns associated with specific human populations, both normal and dysfunctional. (Using QEEG and similar methods.)

4. Intracranial recordings (Loreta) 5. Evoked brain activity, including evoked synchrony and desynchrony. 6. fMRI --- BOLD activity in local cortical regions, e.g., anterior insula.

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A great range of health conditions have been reported to be modifiable by conscious N-feedback.

1. ADD/ADHD in children and adults - using slow cortical potentials 2. Epileptic brain activity 3. Cognitive functions, IQ, and musical performance (JAMA, 2006) 4. Autistic spectrum signs 5. Obsessive-Compulsive Disorder (OCD) 6. Tinnitus (ringing in the ears), and insomnia. 7. Improvements in psychiatric disorders, depression and schizotypy,

auditory hallucinations. 8. Anorexia and bulimia 9. Bladder control, heart-rate, blood pressure,10. Chronic pain, fibromyalgia - cortical pain may depend on slow rhythms.

This is not to say that these are mature, well-tested treatments. However, the very wide range and robust short-term effects are quite remarkable. They tell us something fundamental about consciousness, and suggest important practical applications.

A lot more basic science studies are needed!

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How is this possible? The ideomotor hypothesis.

Ideomotor hypothesis:

Conscious feedback from the brain-triggered visual display is hypothesized to be broadcast globally, and local unconscious motor routines act to plan and trigger voluntary actions --- unless they encounter conscious inhibition.

(Baars, 1988, 2002, etc.)Note: The feedback signal must be conscious, but it doesn’t matter what kind of signal is used - sense modality, pattern, etc.

Conscious image is broadcast ….

Motor regional assembly is triggered by

broadcast image ….

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Neurofeedback training seems to require:

• A distinctive brain signature, linked to the behavior of interest.

• Conscious feedback with minimal time delay. (A few seconds).

•Any kind of conscious feedback stimulus seems to work.

• Minimize distraction and noise.

• The target behavior should not be tightly bound by homeostatic limits. (e.g. heart rate, etc.)

• Gradual steps to the goal.

• Incentives to keep learning, spaced practice sessions over time, adequate sleep and rest periods, and so on.

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Conscious neurofeedback demonstrates exactly the opposite of "epiphenomenalism"

--- the notion that consciousness does nothing useful.

Thomas Henry Huxley - 1874"Darwin's bulldog."

"Epi-phenomena-l-ism" as defined by T.H. Huxley:

"Consciousness would appear to be related to the mechanism of the body … simply as a [side-] effect of its working, and to be completely without any power of modifying that working, as the [sound of] a steam whistle which accompanies the work of a locomotive … is without influence upon its machinery."

The uselessness of consciousness was enormously widespread in behaviorism. Some philosophers and scientists still favor it --- because they don't look at contrastive evidence.

Consciousness is some steam whistle!

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"We know what it is to get out of bed on a freezing morning in a room without a fire,

and how … we say,"I must get up, this is ignominious," etc; but still the warm couch

feels too delicious, the cold outside too cruel, and resolution faints away...

Now how do we ever get up under such circumstances? … We suddenly find that we have got up. A

fortunate lapse of consciousness occurs; we forget both the warmth and the cold;… the (spontaneous) idea

flashes across us, "Hollo, I must lie here no longer" --- an idea which at that lucky instant awakens no

contradictory or paralyzing suggestions, and consequently produces immediately its appropriate motor

effects. ... This case seems to me to contain … the data for an entire psychology of volition. ..." --- William James, 1890, on the ideomotor theory of voluntary control.

William James unable to get off his couch…

William James up and dancing … all because of a

conscious idea!

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James' ideomotor theory fits easily into Global Workspace Theory.

(Baars, 1988, etc) ideomotor theory. The notion that conscious goals and images are inherently impulsive, and tend to be carried out by default, unless they are inhibited by other conscious thoughts or intentions.

This theory can be straightforwardly incorporated into GW theory, and helps to explain basic features of voluntary action … (7.3).

--- Baars, 1988, A Cognitive Theory of Consciousness, Glossary

Bottom line: "Conscious experiences provide the primary adaptive input to the brain: The evidence shows omni-phenomenalism, not epi-phenomenalism.

Conscious experience is very powerful. (Slide 6)

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Basic science questions to be answered.

1. What range of brain events can come under voluntary control? A "Strong GWT" claim suggest that any neuron not under very high local constraints can come under voluntary control.

2. When sensory feedback is UN-conscious but not blocked from sensory receptors, will feedback learning fade in a dose-response fashion? (Strong GWT hypothesis)

Testable prediction: The arbitrary intracranial matrix. In an intracranial grid of electrodes, one should be able to select any arbitrary subset of electrodes to give feedback to, the others being inhibited. (Basmajian, 1961). If that is possible, and if UN-concious perceptual feedback cannot be learned, the implication is that the concious feedback must be very widely distributed.

(GWT)

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Neurofeedback is not the only kind of learning or brain adaptation enabled by conscious experiences…

1. Episodic memory: the MTL-neocortical system involves conscious input and recall.

2. Semantic memory is believed to "ride" on the conscious episodic memory system.

3. Perceptual learning always involves conscious contents.

4. Procedural learning appears to require conscious access during acquisition, and then becomes less conscious with practice, coinciding with less cortical involvement.

5. Experience-dependent plasticity - reorganizes cortex. --- but scientists still avoid the word 'conscious experience'. They also don't run the unconscious controls.

6. Working Memory appears to require consciousness of transitions. (Baars & Franklin, 2003, TICS).

7. There are some demonstrated cases of unconscious input processing and possibly learning. For historical reasons, the professional payoffs are far greater for demonstrating unconscious learning than for consciously-mediated learning. Both are obviously

important.

In sum, the evidence for the role of conscious experiences in brain adaptation is even more widespread than neurofeedback.

Consciously-mediated learning is the norm, not the exception.

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15From Dehaene et al, 2001

Experimental results: Wide forward activation due to conscious visual input, but not unconscious.