Saturday, September 20, 2008

This week’s readings were extremely thought provoking (no pun intended), and in many ways a must read for clinical psychologists. In essence, each article argues for the elimination of the cognition/emotion distinction, providing evidence for the interaction and integration of emotion and cognition, and against the notion of cognition and emotion as separable constructs. The articles immediately brought to mind the current arguments put forth by some in the field against the utility of cognitive therapy – some have proposed deemphasizing cognitive reappraisal in treatments and a move towards more purely behavioral or experiential therapies. When considering the way information about the world and internal states is processed, however, it becomes clear that behavior, cognition, and emotion are so intricately intertwined that a lack of consideration for any one of these domains in therapy in effect results in only a partial picture of the patient’s experience. Each of these articles is summarized below.

1) Duncan, S., & Barrett, L.F. (2007). Affect is a form of cognition: A neurobiological analysis. Cognition and Emotion, 21, 1184-1211.

Duncan and Barret (2007) propose that, while there may be an argument for a phenomenological or functional distinction between cognition and emotion, this distinction should not be confused as an ontological. They begin by a discussion of core affect, which they describe as valence and arousal, and which acts as a “neurophysiologic barometer that sums up the individual’s relationship to the environment” (p. 1186), with self-reported feelings functioning as “barometer readings.” They argue that core affect is in effect core knowledge, and forms the core of conscious experience, serving the primary function of evaluating the potential somatovisceral impact of external stimuli and organizing behavior accordingly. They go on to demonstrate that in addition to subcortical structures traditionally implicated in affective processing (amygdala, ventral striatum, insula), structures traditionally viewed as cognitive (orbitofrontal cortex, ventromedial prefrontal cortex, anterior cingulate cortex) are integral in the computation of the value of stimuli and in coordinating visceral and motor responses. For example, while regions of the amygdala function to evaluate the predictive value of stimuli, the OFC functions to generate an appropriate response based upon that prediction. The article goes on to discuss how sensory processing is widely distributed throughout the brain via interconnected structures, using the example of the amygdala’s role in visual processing. The amygdala can influence visual processing indirectly through top-down control of attention via the dorsolateral prefrontal cortex. The amygdala can also directly enhance visual processing through reciprocal projections to the ventral visual stream, by modulating the intensity of neuronal firing. Finally, the amygdala can influence visual processing directly through connections with regions of the brainstem, in modulating the release of neurotransmitters that in turn enhance sensory processing. Further, Duncan & Barrett point out that core affective circuitry such as the amygdala, OFC, and VMPFC offer the only route by which sensory information reaches the brainstem and basal forebrain. A key way in which the amygdala modulates the processing of visual information is through heightened awareness of stimuli. In essence, the amygdala monitors the affective significance of stimuli, influencing both cortical control of attention and response generation and sensory processing. The authors point out that heightened activation of the amygdala seen anxiety and mood disorders appears to affect sensory processing leading to heightened sensitivity to affective information seen in these disorders. As such, disruptions in core affective circuitry have direct consequences for sensory processing. Sensory information that is deemed to have greater significance to the somatovisceral homeostasis of the individual is preferentially processed, in line with studies reported in Treat & Dirks (2007). Duncan and Barrett go on to demonstrate how core affect influences memory, consciousness, and language, all domains considered to be the domain of cognition. In sum, the article provides an argument for the inseparability of cognition and emotion, showing that all aspects of cognitive processing are integrated with the processing of affective information.

2) Pessoa, L. (2008). On the relationship between emotion and cognition.

Pessoa continues along a similar argument, using evidence from structural connectivity models to demonstrate the interrelationship between “cognitive” and “affective” regions. He argues that while distinctions between anatomical structures considered cognitive versus affective can be made, these structures are highly interconnected, evidencing a greater integration of cognitive and emotional processing than the reliance upon purely anatomical divisions can provide. In fact, following an analysis by Young and colleagues (2000), he suggests the amygdala acts as a central hub in a vast distributed network reaching nearly every region of the brain. He proposes a cognitive-affective control circuit for the processing of information reaching from cortical areas to the brainstem, comprised of the lateral PFC, the OFC, the anterior cingulate cortex, the amygdala, the nucleus accumbens, and the ventral tagmental area. He further proposes that behavior is the result of both affective and cognitive computations. He concludes by proposing we must go beyond looking at interactions between cognition and emotion, and instead consider how cognition and emotion are integrated (how each in effect constrains the other). In essence, Pessoa suggests we consider how both affective information (such as reward properties of stimuli) and cognitive information (such as perceptual processing, attention, and memory) are orchestrated to motivate behavior.

3) Thagard, P. (2008). How cognition meets emotion: Beliefs, desires, and feelings as neural activity. In G. Brun, U. Doguoglu & D. Kuenzle (Eds.), Epistemology and emotions. Aldershot: Ashgate.

Thagard takes a decidedly philosophical point of view, through which he argues for the inseparability of cognition and emotion in epistemology. He points out that traditionally epistemology has ignored emotion, and offers the counter viewpoint that the acquisition and expression of knowledge is inherently affective and therefore inherently emotional (to the extent that one knows something through evaluating the significance of that knowledge to themselves as an individual, or acquires knowledge based upon the motivation or desire to know something). He also argues against conventional views that mental states are propositional attitudes (relations between the self and a proposition), instead suggesting beliefs, desires, and emotions are the result of patterns of neural activity. While much of this article argues an alternative view of epistemology, one major point Thagard makes was well taken. Since knowledge and the acquisition of knowledge are inherently affective, the quest for knowledge and the way that knowledge is processed (perceived or understood) is influenced by the desires and goals of the seeker. This is an important consideration for anyone pursuing scientific knowledge. Given the evidence presented in the previous two papers about the affective influence on information processing, it is important to recognize that the pursuit of knowledge and the interpretation of that knowledge is always intertwined with our own individual beliefs and desires (ie affective motivation). Therefore, we are always operating within our own individual biases. Thus the importance of sharing and collaboration with peers in the quest for scientific knowledge!

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