by Jessica Muzzo
According to Worthman, most sensory processing takes place in the emotion-centered preconscious structures, the limbic system and the thalamus. Emotions are crucial to the preconscious cognitive functions by directing attention and shaping memories through prioritization. The limbic system (the amygdala, hippocampus and associated hormones) are linked both to learning (memory storage) and emotion, thereby affecting what and how things are remembered. Emotion, connecting both conscious and unconscious functions, directs our selective attention by applying significance to sensory inputs. In this way, emotions play a significant role in the construction of meaning.
Worthman points out that studying the effects of this cognitive-emotional liability requires an analysis of the developmental niche, and must consider corporeal and cognitive dimensions. Our physical being regulates individual-environmental interaction as it modulates how our physical and social environments react to us, thereby affecting the situations and experiences we are exposed to. This interactive model accounts for individual variation within a single culture. Under the direction of this model, biology can be seen as the “predisposing factors” that combine with situational risk factors to produce a wide array of outcomes. In dealing with emotional disruptions, such as depression, our society employs both clinical treatment plans (to address the biological components) and public health campaigns (to address the social dimensions).
Our biological predisposition to emotion is termed temperament, and is assumed to be an innate characteristic observable in children. Kagan and colleagues studied “reactive-inhibited” (easily excitable) behavior in young children. He found certain physiological correlates related to reactive personalities, such as high heart rate, low vagal tone and exaggerated cortisol response. Suomi and colleagues established similar physical correlates in rhesus monkeys. They also determined that high-reactive individuals are more greatly affected by their developmental environment than are their low-reactive counterparts. From these rhesus monkey studies, we can conclude that genetic inheritance can influence individual reactivity, and that early experience produces long-term effects under particular conditions and in conjunction with particular temperaments.
This leads us directly to a discussion of the embodied individual-environmental relationship and how it affects health and longevity. For instance, it’s been known that perceived stress can effectively depletes immune response. When investigating reactions to the Loma Prieto eathquake, researchers found that in situations of low parental impact from the earthquake, kindergarten entry produced no significant difference in illness frequency. However, when parents were heavily impacted by the earthquake, high-reactive children saw an increase in illness and low-reactive children saw a decrease in illness. The perceived stress of the children was differentially reacted to, depending on the child’s personal, innate characteristics.
In addition, Worthman shows how hostility and hardship relate to one another. Hostility, in this case, is defined as “a set of negative attitudes, beliefs and appraisal of others” and connotes feelings of being mistreated, frustrated or provoked. This has been related to increased cardiac stress and increased sympathetic activation. Hostility has also been associated consistently and negatively with socioeconomic status.
Worthman sums up her article with a call for more cross-cultural reactivity studies in order to answer such questions as, are there places where high-reactive individuals fare poorly, and others where they fare favorably? She states that cross-cultural understanding of this complex interplay of emotional/reactionary states is lacking, and poses this as one of the primary limitations to the study. She also claims that the inability to develop a causal explanation is a limitation, a statement I disagree with. Neuroanthropology frames itself around an understanding of complexity in that one-to-one ratios are nonexistent. In this endeavor, we must satisfy ourselves with finding correlations and probabilities since a host of factors are constantly interacting to affect the outcome.
Worthman, C. M. (1999). Emotions: You can feel the difference. In Hinton, A., ed. Biocultural Approaches to the Emotions, Cambridge University Press, Cambridge, 41-74.