Dr. Grossi's Blog

BEEMCO: A Ball of Wax

Dr. Philip Grossi
Saturday, 19 March 2011

 

In 1890 William James wrote  The Principles of Psychology  in some of the most lucid English prose ever produced.  In that volume he discussed the impossibility of an approach to emotions which excluded all the accompanying bodily symptoms.  This, he states,  would lead to " a cold and neutral state of intellectual perception."  In this statement he is directing our attention to the fact that psychological states are accompanied by behavioral patterns that include facial expression and a variety of physiological responses. He also states that emotions precede our deliberate reason or intention and are often in direct opposition to them.  He further calls attention to the fact that emotions  profoundly influence cognition.  What follows in this blog is a brief exploration of these influences i.e., the influence of emotion on cognition and behavior (BEEMCO).

illustration to beemco blogFrom an evolutionary standpoint an organism must be able to determine an environment that is more or less advantageous.  The necessity of   assigning a value to events in that environment should be shaped by evolutionary selective processes and should be evident across species. With this frame of reference, emotions represent complex physiological and psychological states which increase in complexity as the environment increases in its demands such as physical, interpersonal, and sociocultural. Therefore, events with large positive or negative valences should show preferential perceptual processing.  Indeed it has been demonstrated that emotional stimuli both positive and negative such as faces that show positive and negative expressions are more rapidly detected as are fear-relevant stimuli such as snakes. Just think about the importance of emotion in everyday experience. It is those experiences that evoke sorrow, happiness, anxiety, pain, etc. that we recall and take note of.

Preferential perception processing is not the only way in which emotional stimuli influence perception.  Attending to stimuli in unattended spatial locations which is often called preattentive can be demonstrated to be influential. A brief target is masked by a second stimulus.  When the hidden target is an emotional item such as an angry face or a snake, preserved processing can be indexed by differential skin conductance responses to fear-relevant with fear-irrelevant targets even though the target stimulus is not perceived.  These findings are bolstered by attentional blink paradigm.  In this situation, detection of an initial target stimulus in a visual stream leads to impaired awareness for a successive target.  This inattentional blindness for the second target is greatly diminished where the second target is an emotional item.  This suggests an advantage for detection of emotional items even when attentional resources are limited.  These findings are supported by study of patients who have certain brain lesions.  While a discussion of those lesions,  and the brain regions involved, is outside the scope of what I intend here, they do support the idea that processing of emotional stimuli occur before the operation of selective attention. 

Privileged perceptual processing of events provide a means of indexing and filing occurrences of value so that they are available to other cognitive domains.  This is clearest in memory, where increased memory for events of value enhances predictability when re-encountering similar events in the future.  Classical conditioning is a good example.  A neutral stimuli, when linked with an aversive one in time, acquires the ability to predict future occurrences of the aversive event. This provides a potential link between psychological mechanisms and psychopathological conditions such as phobias and post-traumatic stress disorder (PTSD). Enhanced autobiographical recall is well documented in anecdotal accounts. You may not remember what you did three weeks ago but you probably remember a constellation of events and feelings when John Kennedy was assassinated or when a parent or a friend died or during the Challenger shuttle catastrophe.

illustration to beemco blogYet this area of emotion and subjective feeling states is difficult to evaluate due to the conflation of mechanisms indexing the occurrence of an emotional event which may include an ensemble of automatic responses, referred to as emotion, and their subjective or experiential counterparts, referred to as feelings.  Feelings are mental representations of of physiological changes that are characteristic of and the result of processing emotional states.  What I am saying is that patterned neural responses differentiate feeling states and that this implies an important causal role for afferent feedback to the brain regarding changes in body status.  The importance of afferent feedback in the experience of emotion is supported by the findings in patients with a rare condition known as pure autonomic failure (PAF) who have failure of peripheral autonomic regulation and consequent emotional blunting. The implications of this division of emotion and feelings is a functional underlying division.  Perception of emotional stimuli results in rapid, automatic, stereotyped emotional responses which stand in contrast to more long-term modulatory behavioral influences which are mediated by feeling states.  This construction in turn implies distinct brain structures and circuits supporting the two distinct states.

In the western philosophical tradition emotion and reason are viewed as distinct and in opposition.  Yet, if we think about this position, we know that emotion can advantageously bias reason and judgment.  Functional neuroimaging studies show the amygdala to be active when individuals make judgment of trustworthiness from facial expressions. Other experiments where the shock expectancy is assessed in fear conditioned and non conditioned individuals shows that those who are better able to detect their heartbeat have enhanced performance in predicting shock state versus non-shock state.  The inference is that predictive judgments and mediated via enhanced awareness of bodily states of arousal.  With regard to emotional contribution to volitional control of behavior, we know that this is dependent of the prefrontal cortex and especially the dorsolateral and dorsomedial areas.  We know that individuals that sustain damage to the ventromedial prefrontal cortex do not suffer intellectual damage but make personally disadvantageous decisions.  The thinking here is that they do not have access to feelings associated with possible scenarios resulting from a contemplated action.

The beginning outlines of the brain areas involved in emotions influencing cognition and behavior is emerging but many questions remain.  How do emotions affect other major axes of experience?  How do they infect rational thought and lead to convictions and beliefs that have no rational basis and which the person cannot change?