The Social Brain: Social Scientists' Construct or Neurological Reality?

ion on our part, a category mistake as it were. After all, the contributors to this book recognize that rather than there being a unified entity called a “self,” the reality is conceptually as well as neuroanatomically extremely messy. For example, the authors of Chapter 21 propose that physical embodiment, cognition, and emotions may together be necessary for “minimal phenomenal selfhood” (p. 326). Additionally, there is neuroimaging and clinical evidence that different dimensions to the self-concept are associated with different processing circuits—for example, self-deception with ventromedial PFC, dorsolateral PFC, and ACC (Chapter 63); self-recognition with inferior frontal gyrus plus inferior parietal and occipital cortex (Chapter 20); self-regulation of ac- tions with inferior PFC and basal ganglia (Chap- ter 48); self-regulation of emotions with PFC and amygdale responses (Chapter 48); and self-serving motives with vental PFC and limbic structures (Chapter 32), among others. Accordingly, given the social nature of humans, many higher-level cognitive functions appear to be wired up by and for specifically social interactions. This hypothesis is consistent with the wide range of self-related functions associated with mPFC noted above. From a neurological point of view, what is it that the so-called “social brain” processes? For one interpretation, the social brain con- structs, encodes, and processes representations of external objects and events, including con- scious agents, intentions and actions, and social attitudes and expectations. Another interpreta- tion is that these encoded representations are not perceptual givens, but are neurally inferred and constructed labels from energy inputs to sensory transducers. This leads to a further question: Without introducing a Gazzaniga-like “Interpreter” or related Homunculus fiction, what information in sensory inputs comes to be labeled social as against nonsocial? Are these even well-defined terms or are they culturally constructed labels? For example, is praying to a stone figurine social interaction? Does talking to one’s ancestral spirits qualify? Playing video games against virtual agents? Writing this review? “Social” may simply belong to what Wittgenstein termed open or loosely textured concepts. Ad- mittedly, not all concepts need be tightly woven. 136 Volume 87 THE QUARTERLY REVIEW OF BIOLOGY This content downloaded from 157.55.39.35 on Fri, 02 Sep 2016 04:22:26 UTC All use subject to http://about.jstor.org/terms However, in the context of this volume, this is a serious drawback, for if the concept “social” is so open-textured as to include aggression and anger, altruism and empathy, attention and at- tention deficits, cognition and comprehension, depression and anxiety, disgust, executive func- tions, guilt, melodies, motivations and rewards, and moral reasoning, then what would not be included? What areas of the brain, whether cor- tical or noncortical, would not be involved? Earlier in this review I listed 11 brain areas most frequently referenced in this publication. If the thousands of social concepts and categories cited in the subject index were mapped onto a large three-dimensional human brain model, I suspect there would be few neural areas not mapped. Either this means that neural process- ing in human beings is, in fact, largely dedicated to social processing, or the concept “social” as used in this volume is way too loosely textured. Given the wide range of nonneuroscience con- tributors to this text, it might be that nearly every- one wants to find some area(s) of the brain on which to map the concepts and issues of their respective research niche and agenda. Obviously, every academic discipline, whether represented in this book or not, invents more and more heu- ristic distinctions and terminology to deal with real or imagined issues. This is as true for the neurosciences as for the social sciences and the humanities. However, why should we assume that the myriad of concepts, distinctions, definitions, and explanatory models associated with the social sciences have counterparts in the brain’s circuitry and processing? How much of social scientists’ descriptive and explanatory modeling conven- tions are simply being projected onto what brains might be processing? As noted earlier, the focus of this volume is “the associations and influences between social and biological levels of organization” (p. 3). In order to identify these associations and influ- ences, the editors are assuming these two dif- ferent levels of organization in fact map onto one another. But why should we assume this? After all, how brains encode and process inputs and outputs have been evolving for millions of years prior to the emergence of complex social organization and the language competencies that made this possible. Accordingly, why should it be assumed that the concepts and distinctions expressed in social language, and language in general, have identifiable neural correlates? Perhaps they have few if any such correlates at all. If we would not expect the brain to have neural correlates for avian taxo- nomical labels such as Gruiformes (cranes), Coraciiformes (kingfishers), and Strigiformes (owls), then why assume there are neural cor- relates for executive function deficits, coping mechanisms, self-esteem defenses, or iterated beliefs? Historically, the concept of an intelli- gent Homunculus or little man in our heads was posited to explain how humans reason, make inferences, and act accordingly. How does this differ in essentials from those neuro- scientists and social scientists in this book who posit a social brain—that is, a socialized Ho- munculus—to explain social behavior? Per- haps an alternate research strategy—one not obvious in the text under review—would be for the social science contributors to this publica- tion to first radically prune their vocabularies to the more elementary foundational aspects of human social behavior (whatever these might be). Once the neural correlates of this initial subset of categories are tentatively identified then—and only then—might additional subtle- ties gradually be introduced. In any case, in spite of these critical comments, I strongly rec- ommend this volume as a timely, albeit contro- versial, reference resource. June 2012 137 NEW BIOLOGICAL BOOKS This content downloaded from 157.55.39.35 on Fri, 02 Sep 2016 04:22:26 UTC All use subject to http://about.jstor.org/terms