Andrea S. Heberlein

Cortical Regions for Judgments of Emotions and Personality Traits from Point-light Walkers

Humans are able to use nonverbal behavior to make fast, reliable judgments of both emotional states and personality traits. Whereas a sizeable body of research has identified neural structures critical for emotion recognition, the neural substrates of personality trait attribution have not been explored in detail. In the present study, we investigated the neural systems involved in emotion and personality trait judgments. We used a type of visual stimulus that is known to convey both emotion and personality information, namely, point-light walkers. We compared the emotion and personality trait judgments made by subjects with brain damage to those made by neurologically normal subjects and then conducted a lesion overlap analysis to identify neural regions critical for these two tasks. Impairments on the two tasks dissociated: Some subjects were impaired at emotion recognition, but judged personality normally; other subjects were impaired on the personality task, but normal at emotion recognition. Moreover, these dissociations in performance were associated with damage to specific neural regions: Right somatosensory cortices were a primary focus of lesion overlap in subjects impaired on the emotion task, whereas left frontal opercular cortices were a primary focus of lesion overlap in subjects impaired on the personality task. These findings suggest that attributions of emotional states and personality traits are accomplished by partially dissociable neural systems.

Ventromedial frontal lobe plays a critical role in facial emotion recognition

The ventromedial prefrontal cortex has been implicated in a variety of emotion processes. However, findings regarding the role of this region specifically in emotion recognition have been mixed. We used a sensitive facial emotion recognition task to compare the emotion recognition performance of 7 subjects with lesions confined to ventromedial prefrontal regions, 8 subjects with lesions elsewhere in prefrontal cortex, and 16 healthy control subjects. We found that emotion recognition was impaired following ventromedial, but not dorsal or lateral, prefrontal damage. This impairment appeared to be quite general, with lower overall ratings or more confusion between all six emotions examined. We also explored the relationship between emotion recognition performance and the ability of the same patients to experience transient happiness and sadness during a laboratory mood induction. We found some support for a relationship between sadness recognition and experience. Taken together, our results indicate that the ventromedial frontal lobe plays a crucial role in facial emotion recognition, and suggest that this deficit may be related to the subjective experience of emotion.

Personhood and Neuroscience: Naturalizing or Nihilating?

Personhood is a foundational concept in ethics, yet defining criteria have been elusive. In this article we summarize attempts to define personhood in psychological and neurological terms and conclude that none manage to be both specific and non-arbitrary. We propose that this is because the concept does not correspond to any real category of objects in the world. Rather, it is the product of an evolved brain system that develops innately and projects itself automatically and irrepressibly onto the world whenever triggered by stimulus features such as a human-like face, body, or contingent patterns of behavior. We review the evidence for the existence of an autonomous person network in the brain and discuss its implications for the field of ethics and for the implicit morality of everyday behavior.

Bioacoustic behavior of African fishes (Mormyridae): Potential cues for species and individual recognition in Pollimyrus

An analysis of the natural bioacoustic signals made by two closely related African fishes (P. adspersus and P. isidori) revealed that these species separated along several acoustic dimensions that are likely to be important for species isolation. Both species produced grunts that were composed of a trains of pulses, but the pulse repetition rates were distinctly different (56 +/- 3 s.d. vs 44 +/- 4 s.d. pps). Complex tone bursts (moans) were also used, but the species differed substantially in the location of the fundamental peak (240 Hz +/- 12 s.d. vs 332 Hz +/- 34 s.d.). Some P. adspersus males sustained these tones for over a second (812 ms +/- 495 s.d.), whereas P. isidori produced shorter tones (121 ms +/- 35 s.d.). During interactions with females, the two species produced the grunts and moans in distinct species-typical patterns: P. adspersus males alternated grunts with moans and P. isidori produced a single grunt followed by a succession of moans. A detailed analysis of identified individual P. adspersus showed that acoustic features constituted individual signatures which could be used by conspecifics to identify individuals. Grunt spectral peak frequency was shown to be a good predictor of male mass, with peak frequency decreasing at 72 Hz per gram. Simulated standardized courtship encounters with females revealed that males differ markedly in their apparent ability to produce sustained moans and it is suggested that this may be particularly important to females in mate selection.

Method Matters: An Empirical Study of Impact in Cognitive Neuroscience

A major thrust of cognitive neuroscience is the elucidation of structure-function relationships in the human brain. Over the last several years, functional neuroimaging has risen in prominence relative to the lesion studies that formed the historical core of work in this field. These two methods have different strengths and weaknesses. Among these is a crucial difference in the nature of evidence each can provide. Lesion studies can provide evidence for necessity claims, whereas functional neuroimaging studies do not. We hypothesized that lesion studies will continue to have greater scientific impact even as the relative proportion of such studies in the cognitive neuroscience literature declines. Using methods drawn from systematic literature review, we identified a set of original cognitive neuroscience articles that employed either functional imaging or lesion techniques, published at one of two time points in the 1990s, and assessed the effect of the method used on each articles impact across the decade. Functional neuro-imaging studies were cited three times more often than lesion studies throughout the time span we examined. This effect was in large part due to differences in the influence of the journals publishing the two methods; functional neuroimaging studies appeared disproportionately more often in higher impact journals. There were also differences in the degree to which articles using one method cited articles using the other method. Functional neuroimaging articles were less likely to include such cross-method citations.

Distortions of mind perception in psychopathology

It has long been known that psychopathology can influence social perception, but a 2D framework of mind perception provides the opportunity for an integrative understanding of some disorders. We examined the covariation of mind perception with three subclinical syndromes—autism-spectrum disorder, schizotypy, and psychopathy—and found that each presents a unique mind-perception profile. Autism-spectrum disorder involves reduced perception of agency in adult humans. Schizotypy involves increased perception of both agency and experience in entities generally thought to lack minds. Psychopathy involves reduced perception of experience in adult humans, children, and animals. Disorders are differentially linked with the over- or underperception of agency and experience in a way that helps explain their real-world consequences.

Neuroscientific Evidence for Simulation and Shared Substrates in Emotion Recognition: Beyond Faces

According to simulation or shared-substrates models of emotion recognition, our ability to recognize the emotions expressed by other individuals relies, at least in part, on processes that internally simulate the same emotional state in ourselves. The term “emotional expressions” is nearly synonymous, in many peoples minds, with facial expressions of emotion. However, vocal prosody and whole-body cues also convey emotional information. What is the relationship between these various channels of emotional communication? We first briefly review simulation models of emotion recognition, and then discuss neuroscientific evidence related to these models, including studies using facial expressions, whole-body cues, and vocal prosody. We conclude by discussing these data in the context of simulation and shared-substrates models of emotion recognition.

Perception of socially relevant stimuli in schizophrenia

To examine whether patients with schizophrenia have deficits in the appraisal of socially relevant stimuli, we tested 20 patients and 14 healthy volunteers equated for parental socioeconomic status on recognition of gender stimuli, emotional people stimuli, and emotional scenes. Patients with schizophrenia showed deficits in discrimination of subtle gender differences and in the identification of emotion from human shapes and body motion. Patients showed no impairment on measures of hedonic appraisal of emotional scenes and recognition of emotional expression in human face stimuli. Across tasks, subjects with schizophrenia showed poorer identification of happiness, anger, and fear. The findings point towards circumscribed domains of impaired social cognition in schizophrenia and suggest specific further hypotheses about the neural dysfunction that may underlie them.

Spared ability to recognise fear from static and moving whole-body cues following bilateral amygdala damage

Bilateral amygdala lesions impair the ability to identify certain emotions, especially fear, from facial expressions, and neuroimaging studies have demonstrated differential amygdala activation as a function of the emotional expression of faces, even under conditions of subliminal presentation, and again especially for fear. Yet the amygdalas role in processing emotion from other classes of stimuli remains poorly understood. On the basis of its known connectivity as well as prior studies in humans and animals, we hypothesised that the amygdala would be important also for the recognition of fear from body expressions. To test this hypothesis, we assessed a patient (S.M.) with complete bilateral amygdala lesions who is known to be severely impaired at recognising fear from faces. S.M. completed a battery of tasks involving forced-choice labelling and rating of the emotions in two sets of dynamic body movement stimuli, as well as in a set of static body postures. Unexpectedly, S.M.s performance was completely normal. We replicated the finding in a second rare subject with bilateral lesions entirely confined to the amygdala. Compared to healthy comparison subjects, neither of the amygdala lesion subjects was impaired in identifying fear from any of these displays. Thus, whatever the role of the amygdala in processing whole-body fear cues, it is apparently not necessary for the normal recognition of fear from either static or dynamic body expressions.

Contrasting roles for lateral and ventromedial prefrontal cortex in transient and dispositional affective experience

Prefrontal cortex (PFC) has been implicated in the experience and regulation of emotional states. Emotional experience is a complex construct, encompassing a range of more specific processes. This exploratory study aimed to delineate which (if any) aspects of emotional experience rely critically on either the ventromedial frontal (VMF) or lateral frontal (LF) lobes. The affective experience of individuals with damage to these regions was surveyed in detail using several measures and compared with that of control participants. Dependent measures included subjective and observer ratings of both dispositional affect and transient responses to laboratory mood inductions. VMF damage was associated with greater negative dispositional affect relative to controls and to individuals with LF damage; however, transient responses to emotional stimuli were largely normal. In contrast, LF damage was associated with an exaggerated subjective reactivity to sad emotional stimuli relative to control participants, but normal dispositional affect. Interestingly, neither form of PFC damage affected spontaneous emotion recovery following the mood inductions. These findings suggest a role for VMF in modulating dispositional negative affect; in contrast, LF areas appear to be critical in regulating transient emotional responses while emotional stimuli are present. This study also illustrates the dissociability of different aspects of emotional experience in patients with focal brain injury.