Social Neuroscience

Key Readings

John T. Cacioppo, Gary G. Berntson

• Publisher: Psychology Press
• Year: 2013
• Print ISBN:
  9781841690995
• eBook ISBN:
  9781136979231
• Topic: Psychology
• Subtopic: History & Theory in Psychology
• Index: Psychology

Neuroscientists and cognitive scientists have collaborated for more than a decade with the common goal of understanding how the mind works. These collaborations have helped unravel puzzles of the mind including aspects of perception, imagery, attention and memory. Many aspects of the mind, however, require a more comprehensive approach to reveal the mystery of mind-brain connections. Attraction, altruism, speech recognition, affiliation, attachment, attitudes, identification, kin recognition, cooperation, competition, empathy, sexuality, communication, dominance, persuasion, obedience, morality, contagion, nurturance, violence, and person memory are just a few. Through classic and contemporary articles and reviews, Social Neuroscience illustrates the complementary nature of social, cognitive, and biological levels of analysis and how research integrating these levels can foster more comprehensive theories of the mechanisms underlying complex behaviour and the mind.

PART 1

Volume Overview Analyses of the Social Brain through the Lens of Humen Brain Imaging

John T. Cacioppo • University of Chicago
Gary G. Berntson • The Ohio State University

Among the major evolutionary advances in humans is the striking development of the human cerebral cortex, especially the frontal and temporal regions. The cerebral cortex is a mantle of between 2.6 to 16 billion neurons with each neuron receiving 10,000 to 100,000 synapses in their dendritic trees (e.g., Pakkenberg, 1966). The frontal and temporal lobes constitute 32% and 23% of the cerebral cortex, respectively, rendering the sensorimotor cortices that dominate most mammalian brains to minority status in the human brain. The expansion of the frontal regions in the human brain is largely responsible for the human capacity for reasoning, planning, and performing mental simulations, and an intact frontal region contributes to the human ability to reason, remember, and work together. The temporal regions, in turn, play essential roles in social perception and communication. The neocortex, in particular, is a recent development in evolutionary time, and the means for guiding behavior through the environment, albeit in a more rigid and stereotyped fashion, emerged prior to neocortical expansion. These evolutionarily older systems likely also play a role in human information processing and behavior (Berntson, Boysen, & Cacioppo, 1993; Smith et al., 2003).

Human information processing capacities remain woefully insufficient even with the expansion of the cortices, however. The sensory load from the physical environment is minor in comparison to the quantity and complexity of the information that comes from other individuals, groups, alliances, and cultures—as well as the potential for benevolence or treachery from each. It is perhaps understandable why social cognition is not an objective information process but instead is rife with the operation of self-interest, self-enhancement, and self-protective processes (Cacioppo & Berntson, 2004). For instance, because there is more information than can possibly be processed, people tend to search for and attend to evidence that confirms what they already believe to be true (Snyder & Swann, 1978). Information processing is biased in ways that protects the self from symbolic as well as actual threats and promotes reproductive success (e.g., Jones & Berglas, 1978). People believe they know how long things they choose will make them feel good or bad, but in fact they grossly overestimate the duration of these feelings (Wilson et al., 2000). Subtle reminders of their mortality can push people to promote defensive information processing, such as blaming the victim and enacting risky behaviors, as if to prove to themselves that the world is just and threats do not apply to them (Pyszczynski, Greenberg, & Solomon, 1999). In fact, people are not particularly good at knowing the causes of their feelings or behavior (Nisbett & Wilson, 1977). They believe they know that opposites attract, just as assuredly as they know that its logical opposite is also true (i.e., birds of a feather flock together). People overestimate their strengths and underestimate their faults (Ross & Sicoly, 1979); they overestimate how important is their input, how pervasive are their beliefs, and how likely is a desired event to occur (McGuire, 1981), all while underestimating the contributions of others and the likelihood that risks in the world apply to them (Ross, Greene, & House, 1977). Events that unfold unexpectedly are not reasoned as much as they are rationalized (Aronson, 1968), and the act of remembering is far more of a biased reconstruction than an accurate record of actual events (Roediger, Buckner, & McDermott, 1999; McDonald & Hirt, 1997). Mental simulation of alternative outcomes—made possible through the expansion of the frontal cortices—can dramatically influence our evaluations and decisions, so much so that the counterfactual reasoning of silver medalists in the Olympic Games leave them, on average, less happy with their achievements than bronze medalists (Medvec, Madey, & Gilovich, 1995). These biases in social cognition are automatic in the sense that they are spontaneous, their implementation does not require cognitive effort, and they are ubiquitous in that they represent normative processing. They represent emergent properties from the operation of the human brain, sculpted by adaptive and reproductive successes and failures (Cacioppo & Berntson, 2004).

During most of the past century, the nuances of social cognition and social processes, including unconscious processes, were plumbed through the clever experimental designs and measures of verbal reports, judgments, and reaction time. These methodologies were limited in what they could reveal about social processes, however. Social cognition and behavior are often affect-laden or habitual, and nuances deriving from these features proved difficult to capture fully using subjective measures and response latencies to semantic (e.g., lexical decision) tasks (Zajonc, 1980). In a recent Annual Review of Neurosciences, LeDoux observed:

It is widely recognized that most cognitive processes occur unconsciously, with only the end products reaching awareness, and then only sometimes. Emotion researchers, though, did not make this conceptual leap. They remained focused on subjective emotional experience … The main lesson to be learned … is that emotion researchers need to figure out how to escape from the shackles of subjectivity if emotion research is to thrive. (LeDoux, 2000, p.156)

The same is true in social psychology (Berntson & Cacioppo, 2000; Cacioppo & Berntson, 1992, 2004). The study of automatic and implicit processes became popular in social psychology in the 1990s, but as important as these developments were, the richness of the information provided remained quite limited. The purpose of this book is to introduce students to a new and developing approach to address these questions—an approach termed social neuroscience (Cacioppo & Berntson, 1992).

In social neuroscience, theory and methods in the neurosciences constrain and inspire hypotheses in the behavioral and social sciences, foster experimental tests of otherwise indistinguishable theoretical explanations, and increase the comprehensiveness and relevance of social and behavioral theories. Whereas a measure of reaction time may provide information about differences in the time it takes to perform specific mental operations, metabolic and electrophysiological images of brain activity may provide moment by moment information about when and where social cognition is unfolding in the brain, and from this one can infer what is the nature of the information processing operation being performed moment by moment in the brain. Parallel series of information processing operations, in theory, are as tractable as a single series of information processing operations—making it possible to examine the brain as it does two (or more) things at the same time.

The field of social neuroscience stretches far beyond social cognition, human studies, or brain imaging methodologies (see Cacioppo et al., 2002). Rather than canvassing the full scope of social neuroscience, however, we selected the current readings to illustrate work within a limited area that is shaping scientific thought about a classic question in social psychology: Is there anything special about “social” cognition? We next review illustrative evidence bearing on this question to provide a context for the readings that follow.

Social Processes and Behavior: Multipurpose or Specialized Neural Mechanisms

One of the fundamental questions in the field is whether specific social constructs, processes, and representations have a definable neural locus. Is social information processed by specialized neural circuitry? Two complementing strategies are typically used to address this question: (1) one can examine the function or functions associated with a particular neural locus or region to determine if it exclusively serves social information processing, or (2) one can place the focus on a specific social process or function to examine the different ways in which this function might be achieved.

In a seminal thesis based primarily on neurophysiological recordings in nonhuman primates, Brothers (1990) proposed that the superior temporal sulcus (STS) is involved in integrative processing of conspecifics’ behavior, and the amygdala and orbitofrontal cortex are subsequently involved in specifying the socioemotional relevance of social information. Kanwisher (e.g., Kanwisher, 2000; Kanwisher, McDermott, & Chun, 1997), using functional magnetic resonance imaging (fMRI) data, emphasized the role of the fusiform gyrus in face processing, and Damasio and colleagues (e.g., Damasio, 1994), focusing primarily on data from humans with brain lesions, have emphasized the role of the frontal (ventromedial prefrontal, orbitofrontal) cortex, amygdala, and somatosensory cortex (insula, SI, SII) in social perception, cognition, and decision-making. Adolphs (2003, see Figure 1) has drawn from these literatures and brain lesion data to suggest that social cognition draws upon neural mechanisms for perceiving, recognizing, and evaluating stimuli, which are then used to construct complex central representations of the social environment. These central processes involve the fusiform gyrus and the STS in the temporal region, as well as the amygdala, orbitofrontal cortex, anterior and posterior cingulate cortices, and right somatosensory-related cortices. Like nonsocial information processing, the central processes of social cognition modulate effector systems including the motor and premotor cortices, basal ganglia, hypothalamus, and periaqueductal gray.

Figure 1 Processes and brain structures that are involved in social cognition. It is possible to assign sets of neural structures to various stages of information processing However, the flow of social information defies any simple scheme for at least two reasons: It is multidimensional and it is recursive. A single process is implemented by a flexible set of structures, and a single structure participates in several processes, often during distinct windows of time. Processing routes differ in terms of their automaticity, cognitive penetrability, detail of the representations they involve, and processing speed. The structures outlined in this figure share some core features of a social information processing system: selectivity (they make distinctions between different kinds of information), categorization and generalization, and the incorporation of past experience. Several of the components of social cognition (inside the gray shaded area) contribute to social knowledge. Reappraisal and self-regulation are particular models of feedback modulation whereby evaluation and emotional response to social stimuli can be volitionally influenced.

(From Adolphs, R. [2003]. Neuroscience Reviews, 4, 165–178 With permission.)

Disputes have emerged, however, regarding whether certain nuclei (e.g., fusiform gyrus) function to process social information (e.g., faces; Kanwisher, 2000) or more generic forms of information (e.g., objects about which there is expertise; Gauthier et al., 2000; cf. Farah et al., 1998) and about the specific contribution to social cognition made by various nuclei. These disputes depend in part on the conceptualization of brain localization and what it is that is localized.

The adaptive value of social recognition and communication contributed to the evolution of the human brain’s preparedness for facial recognition and language acquisition, but these same information-processing operations may be useful in all kinds of information processing tasks confronting people in contemporary societies. However, the evolutionary function or functions that led to the rise of a particular neural system in the human brain do not place strict constraints on the stimuli, tasks, or functions that may be served today by the system. That is, a structure that already exists can take on a new function, or an established process may be co-opted for other purposes. This extended adaptation of an existing structure or system is termed exaption and may contribute to the appearance that there is nothing special in the brain regarding social cognition.

Ideas about the anatomical basis of functional localization in the cortex have been debated for hundreds of years, until research on primary sensory cortices (e.g., Munk, 1881; Tunturi, 1952) and on somatosensory regions (e.g., Schaltenbrand & Woolsey, 1964) refuted the hypothesis that the brain was a homogeneous tissue that depended on total mass to carry out functions. The more recent discovery of mirror neurons in monkeys also cautions against a premature assignment of function to structures, and at the same time illustrates the potential brain localization of social information processing. Mirror neurons are a class of neurons in the ventral premotor cortex of monkeys (area F5, among others) that become active when the monkey makes a particular action or when it observes another individual making a similar action (Rizzolatti, Fogassi, & Gallese, 2001). The same neurons also respond on perceiving an object that affords specific kinds of motor behaviors (Grezes & Decety, 2002; Rizzolatti & Fadiga, 1998), but they do not otherwise tend to respond to the presentation of an object of an action, or to the mimicking of an action in the absence of the object. Kohler et al. (2002) recorded from individual neurons in the F5 area of monkeys homologous to Broca’s area in humans. They found that individual neurons responded when the monkey performed specific motor behaviors, when the monkey observed other individuals performing the same behavior, and when the monkey heard but could not see the same behavior being performed by another. These results indicate that visual and audiovisual mirror neurons code not the visual analysis of the action per se but the goal and meaning of the actions of both oneself and others, as well as the perspective one takes on those actions (Ruby & Decety, 2001). Studies employing fMRI suggest that similar functions may also be represented in the premotor cortex of humans (Grezes et al., 2003).

Recall that the somatosensory cortices dominate most mammalian brains but in the human brain the frontal and temporal lobules constitute over half the cerebral cortex. The well-defined localization of sensory and motor functions poses as a hypothesis but does not prove that more complex integrative processing by the brain is similarly compartmentalized. Brothers (1990), for instance, suggested that the amygdala was an essential component of a set of nuclei involved in social cognition. The evidence that led to this suggestion is illustrated by Dicks, Myers, and Kling (1969), who subjected a sample of free-roaming rhesus monkeys to bilateral amygdalectomy before returning them to their social groups. Dicks et al. (1969) found that these monkeys invariably were ostracized and most perished without the support of their troop. This led to the view that the amygdala was essential for the normal perception and production of expressive displays and behaviors, and that damage to the amygdala undermined an animal’s capacity for effective social interactions.

Using macaque monkeys, Amaral and colleagues (Amaral et al., 2003; Prather et al., 2001) examined the role of the amygdala in social cognition using a more circumscribed lesion of the amygdala and quantitative measures of dyadic social interactions. Amaral et al. (2003) observed the social behavior of monkeys with ibotenic acid lesions of the amygdala and controls matched for age, sex, and dominance. Results revealed that the lesion of the amygdala appeared to have produced a socially uninhibited monkey. For instance, the lesioned monkeys did not go through the normal period of evaluation of the other monkeys before engaging in social interactions. As a result, the lesioned monkeys initiated greater amounts of affiliative social behavior than the control monkeys. Amaral et al. (2003) also found differences in how the control animals interacted with the lesioned animals. Rather than shunning the lesioned monkeys because of their early and non-normative forwardness toward the control monkeys, the control monkeys generated more affiliative social behaviors toward the lesioned than the control monkeys. “The inevitable conclusion from this study is that in dyadic social interactions, monkeys with extensive bilateral lesions of the amygdala can interpret and generate social gestures and initiate and receive more affiliative social interactions than controls” (Amaral et al., 2003, p. 238). Amaral and colleagues have posited that the amygdala functions to suppress the engagement of objects and conspecifics while an evaluation of the potential threat is conducted. In the absence of a functioning amygdala, conspecifics are not regarded as potentially dangerous or the social context is regarded as safe, and, hence, social interactions are engaged.

Amaral et al. (2003) further reviewed evidence that the amygdala plays this role in threat appraisals generally, not only in the evaluation of potential dyadic partners. The latency to retrieve a food reward from in front of a stimulus object is slowed in normal animals when the stimulus has fear-provoking qualities (e.g., rubber snake), but the latency of lesioned monkeys was not altered by potential dangers in the environment. Prather et al. (2001) evaluated whether the amygdala was essential not for the emission of social behaviors but for the learning of social behaviors. Young monkeys underwent the same bilateral lesion of the amygdala at 2 weeks of age. Steps were taken to insure opportunities for normal social development and to avoid the behavioral differences associated with nursery rearing. Results reveal interactions with the mother that are similar for lesioned and control animals. The lesioned animals also showed little fear of normally fear-provoking objects (e.g., rubber snake), although they did show more less social interaction and more fear grimaces, screams in novel dyadic social interactions. Most social behaviors, however, were indistinguishable between lesioned and control animals.

In sum, the question is not whether, but where and how activity in the brain serves a social process that has the potential to inform theory in the social and brain sciences. The research on the essential role of the amygdala in social cognition is illustrative of the general thesis that, even though the dramatic expansion of the human brain may have been fueled by the com...

Table of contents

• Cover
• Half Title
• Full Title
• Copyright
• Contents
• About the Editors
• Acknowledgments
• Preface
• PART 1. Volume Overview: Analyses of the Social Brain through the Lens of Humen Brain Imaging
• PART 2. The Brain Determines Social Behavior: The Story of Phineas Gage
• PART 3. Dissociable Systems for Attention, Emotion, and Social Knowledge
• PART 4. Dissociable Systems for Face and Object Processing
• PART 5. Dissociable Systems for the Perception of Biological Movement
• PART 6. Biological movement: From Perception to Imitation to Emotion
• PART 7. Animacy, Causality, and Theory of Mind
• PART 8. Social Perception and Cognition: Multiple Routes
• PART 9. Decision Making
• PART 10. Biological Does Not Mean Predetermined: Reciprocal Influences of Social and Biological Processes
• Appendix: How to Read a Journal Article in Social Psychology
• Author Index
• Subject Index