COGNITIVE SCIENCE 175



COGNITIVE SCIENCE 175

Spring Quarter

Midterm I

Answer only 4 of the questions. Each is worth 25 points. Make sure to write your name at the top of each page. Don’t forget to provide examples from class readings.

1. Is hypnosis a distinct state of consciousness? Why or why not? What are the behavioral correlates of hypnosis (i.e., how is a hypnotic state defined behaviorally)? What are some of its neural substrates?

Hypnosis is a distinct state of consciousness. In a hypnotic state people process information differently, interact with the environment differently and have different representations of themselves and of the world when compared to a normal state of awareness. Under hypnosis it has been reported that bad habits can be treated, phobias can be overcome, and the sensation of pain can be regulated. According to the trance theory of hypnosis, people enter an altered trance-like state in which they are highly susceptible to suggestion. Other theories, specifically the sociological and task-motivation theories argue that one’s willingness to play a role and eagerness to please are what characterizes hypnosis as not being an altered state of consciousness.

Behavioral correlates of hypnosis are best summed up by Price’s dimensions of this state: 1) increased mental relaxation 2) increased mental absorption 3) decreased tendency to judge 4) loss of time, orientation, and sense of self 5) automatic or extravolitional responses. In general, people under hypnosis are extremely relaxed, have focused attention, and are very open to suggestion.

Faymonville and Rainville have shown that there are neural substrates underlying these behavioral phenomena. In studies on nociception, Faymonville argued that the midcingulate cortex has enhanced neuromodulatory activity that reduces the perception of pain under hypnosis. In a network including somatosensory cortex, the thalamus and the brainstem, the midcingulate cortex increases inhibition of pain. Rainville showed support for the same structures underlying the relaxing and attentional processes under hypnosis. Decreased rCBF in the thalamus and the brainstem correlates with increased relaxation. Ascending cholinergic pathways controlling sleep and wakefulness may be involved. In other parts of the thalamus and in the upper pons, increased rCBF correlates with highly focused attention. In light of these studies and the observations of hypnotized people, hypnosis is clearly a distinct state of consciousness.

2. The role of dopamine in the concept of reward and drug addiction has changed significantly during the last few years to one based more on changes in cognitive processes. Discuss this new view and its significance to alternate states of consciousness.

In the “new view” on dopamine reward and drug addiction, dopamine is still associated with reward and motivation but a new emphasis is also put on dopamine’s role in processing saliency. Drug addiction affects reward and saliency in the following ways: when a drug is first administered, there is a large amount of DA released by the nucleus accumbens – a much larger amount than is released in natural reward situations (i.e., eating cheesecake). Despite this initial high level of DA, long-term drug use actually results in a decrease in total dopamine production as well as a decrease in D2 receptors. This means that natural reinforcers (like cheesecake, everyday achievements, etc), which do not result in as much DA output as the drug, are no longer rewarding/salient. In addition, the drug itself takes on increased saliency. Furthermore, drug-induced changes in frontal cortex and the cingulate result in inability to inhibit behavior, which means that the person will continue to use the drug even though they are cognitively aware of the negative consequences this may entail (for example, going to jail). People who naturally have lower D2 receptor levels will find drugs more salient/rewarding and are more likely to use them, while people with higher D2 levels experience unpleasant overstimulation as a result of the DA released in drug use. There are several implications for ASC’s:

1) The same stimulus can affect different people’s conscious experience differently depending on their brain structure, which implies there is individual variation in consciousness;

2) 2) ASC’s are associated with changes in the brain’s synaptic structure and neurochemical balance as well as with behavioral changes.

3. How would you reconcile the following observations: “Alternate states of consciousness (ASCs) are principally due to frontal cortex activity. However, a large body of evidence from lesion, imaging, and electrophysiological studies suggests that the prefrontal cortex is not necessary for basic awareness. In contrast, lesions to various brainstem nuclei or the intralaminar nuclei of the thalamus result in the loss of awareness.”

This observation can be reconciled by Dietrich’s theory of a hierarchically organized consciousness. He believes that prefrontal cortex plays an important role in consciousness, but that consciousness is a phenomenon that involves the whole brain. Dietrich’s theory is based on evolutionary factors. Thus our primitive brain, such as the midbrain and hindbrain, are lower in the hierarchy and the cortex and its lobes (temporal, occipital, frontal, parietal) are higher in the hierarchy. Dietrich claims that all regions of the brain contribute to a person’s consciousness, but not all regions contribute equally. He claims prefrontal cortex is important because it is implicated for phenomena such as memory, planning, theory-of-mind, attention, social interaction and other higher-order functions which make a person “conscious.” Basic awareness, on the other hand, is at a lower level of the hierarchy. So, the lower down you go (in terms of damaging a region) the more you are fundamentally going to affect awareness and more basic, primitive functions like it. Consciousness is based higher on the hierarchy with the prefrontal cortex contributing a vast amount and the other lobes contributing as well. Thus, althougnh prefrontal cortex is not responsible for basic awareness, it is involved in this higher-order concept of consciousness and alternate states. Diff alternate states are simply caused by different activation and circuits in the frontal lobe.

4. Discuss what might be the relationship between ASCs and periods of synchronous activity represented by certain electric potential patterns on the scalp.

Alternate states can be thought to relate to electrical rhythms found on the scalp (in addition to the anatomical and neurochemical descriptions discussed earlier). These different frequencies appear to relate to different mental states and cognitive functions. According to Pineda, the mu rhythm is an alpha-type rhythm found primarily above motor cortices and correlates to motor action, observation and thought in the individual. According to Vernon, the theta rhythm is a slow rhythm which correlates with working memory and the SMR is found over sensorimotor areas and correlates with attention. Theta rhythms have also been implicated in “internal” states and processes such as meditation or deep contemplation. Because of the cognitive implications of these brain rhythms, it is reasonable to conclude that ASC’s may be modulated by increases or decreases of certain rhythms w/in certain areas of the brain. This may actually validate or support some of the anatomical research that rhythm generators correspond to defined areas in the brain.

5. Discuss what makes individuals more or less susceptible to different methods that create distinct states of consciousness (i.e., drugs, hypnosis, biofeedback). What might be the similarities or differences across the various ASCs.

Individuals may be more susceptible to different methods of altering consciousness for many reasons. Hypnosis, for example, works best on highly suggestive people, there is even a standardized test to determine susceptibility called the Stanford Susceptibility Test, which can determine level of suggestiveness based on answers to particular questions. Biofeedback also involves using individuals who are more likely to respond, such as highly attentive individuals. I feel that attention plays the largest role in determining susceptibility due to William James’ definition of alternate states of cons. He suggests that there is a selective filter of consc. In hypnosis, the task-motivational theory suggests that hypnosis occurs only because the individuals are simply choosing to attend to what the hypnotist is saying. So there is a high level of attention involved. In biofeedback, as well, the individuals are simply choosing to focus all attentional resources on certain inward functions, thus being able to alter their state internally. With drugs, however, I don’t believe that attention plays a big role. Individuals may have a propensity toward drug addiction due to many factors, however, mainly either social factors or possible family history of addiction, which suggests a gene mutation. So I feel that both hypnosis and biofeedback susceptibility depends mainly on an individual’s ability to focus attentional resources to enter an alternate state of consciousness. But, drug addiction depends more on neural organization and social propensity.

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