Emotional expression and physiology in European Americans and Hmong Americans

Ethnographic and clinical observations suggest that Asians are less expressive than European Americans. To examine whether this difference emerged in online emotional responding, 50 Hmong Americans (HAs) and 48 European Americans (EAs) were asked to relive past episodes of intense happiness, pride, love, anger, disgust, and sadness. Facial behavior and physiological reactivity were measured. For most emotions, more cultural similarities than differences were found. There were some exceptions: During happiness, fewer HAs than EAs showed non-Duchenne smiles (i.e., "social" smiles), despite similarities in reported emotional experience and physiological reactivity. Within-group differences between "less Hmong" and "more Hmong" HAs were also found. Implications of these findings for our understanding of culture-emotion relations are discussed.     

Frames of reference for human perceptual-motor coordination: space-based versus joint-based adaptation

In this study, the authors addressed the issue of whether space-based motor planning occurs at a higher, equal, or lower level of central nervous system control than joint-based motor planning by using a computerized adaptation paradigm. Visual displays of participants' (N = 32) reaching movements to spatial targets were distorted either with respect to spatial hand displacements (space-based distortion) or with respect to joint angle displacements (joint-based distortion). Participants adapted more easily to space-based distortion than to joint-based distortion. The results suggest that when the participants were confronted with new visuomotor mappings, they aimed for virtual spatial targets whose positions were adjusted to compensate for the distortions associated with the new mappings. That strategy was preferred over a joint- or posture-based strategy, in which a posture is selected for the displayed spatial target and is then modified so that the new mapping between adopted and seen positions can be accommodated. The results support the widely held view that space-based planning occurs at a higher level than joint-based planning.     

The Cinderella of psychology: the neglect of motor control in the science of mental life and behavior

One would expect psychology--the science of mental life and behavior--to place great emphasis on the means by which mental life is behaviorally expressed. Surprisingly, however, the study of how decisions are enacted--the focus of motor control research--has received little attention in psychology. This article documents the neglect and considers possible reasons for it. The hypotheses considered include three that are raised and then rejected: (a) no famous psychologists have studied motor control, (b) cognitive psychologists are mainly interested in uniquely human functions, and (c) motor control is simply too hard to study. Three other hypotheses are more viable: (d) cognitive psychologists have been more interested in epistemology than in action, (e) psychologists have disfavored motor control because overt responses were the only admissible measure in behaviorism, and (f) psychologists have felt that neuroscientists have the market cornered when it comes to motor control research. There are signs that motor control's Cinderella status is changing.     

On the relation between maternal state of mind and sensitivity in the prediction of infant attachment security

Attachment theorists assume that maternal mental representations influence responsivity, which influences infant attachment security. However, primary studies do not support this mediation model. The authors tested mediation using 2 mother-infant samples and found no evidence of mediation. Therefore, the authors explored sensitivity as a moderator, studying the (a) interaction of mental representation and sensitivity as it predicts infant attachment security and (b) level of sensitivity in mothers whose infants' attachment security is either concordant or discordant with their own. The interactional analyses were not significant. But the match-mismatch data showed that when mother-infant attachment strategies were discordant, maternal sensitivity was more consistent with infant than maternal attachment strategy. These findings are congruent with an interpretation of sensitivity as a moderator that can block transmission of attachment strategy.     

Clinical status of at-risk individuals 5 years later: further validation of the psychometric high-risk strategy

The authors hypothesized that at-risk individuals identified on the basis of their Chapman scale scores would be diagnosed with schizophrenia-spectrum disorders at follow-up. In the present study, the authors interviewed 135 young adults approximately 5 years following their initial assessment. The at-risk groups included high scorers on the Perceptual Aberration and/or Magical Ideation Scales (n=59) and high scorers on the revised Social Anhedonia Scale (n=32). The control participants (n=44) scored below 0.5 SD of the same-sex group means on all the scales. At the follow-up, the groups differed in terms of their likelihood of having a schizophrenia-spectrum diagnosis, Chi2(2)=9.79, p<.01. The at-risk groups reported more frequent and severe psychotic-like experiences relative to the control group. These findings support the predictive validity of the Chapman psychosis-proneness scales and may enhance the power of early detection efforts.     

Concurrent second-order schedules: some effects of variations in response number and duration

To examine the effects on concurrent performance of independent manipulations of response-unit duration and number, 6 hens were exposed to concurrent second-order schedules of reinforcement. Each first-order operant unit required completion of a fixed-ratio schedule within the time specified by a fixed-interval schedule, with one further response completing the fixed-interval schedule. The fixed-ratio and fixed-interval requirements comprising the first-order operant units were systematically and independently varied under three pairs of concurrent variable-interval schedules to produce differences in the first-order response and duration requirements (response and duration differentials). These manipulations produced consistent changes in response, time, and operant-unit biases. A 1:4 response differential biased the time and operant-unit measures towards the smaller fixed ratio, but to a degree less than the imposed response differential. The response-based biases favored the larger fixed ratio. Duration differentials of 4:1 and 8:1 biased the response and operant-unit measures towards the shorter fixed interval, again less than the imposed duration differential, but the time biases remained close to zero. Both sorts of differentials acted to bias operant-unit completions more systematically than the other measures, but undermatching to the differentials occurred. The undermatching appears to have arisen from a pattern of fix and sample (in which visits to the less preferred alternative involved only a single completed operant unit) under combinations of unequal operant-unit requirements and reinforcer rates. The response and time bias measures appeared to arise as by-products of the changes in operant-unit completions.     

Enemies and friends in the neighborhood: orthographic similarity effects in semantic categorization

Studies investigating orthographic similarity effects in semantic tasks have produced inconsistent results. The authors investigated orthographic similarity effects in animacy decision and in contrast with previous studies, they took semantic congruency into account. In Experiments 1 and 2, performance to a target (cat) was better if a previously studied neighbor (rat) was congruent (i.e., belonged to the same animate-inanimate category) than it was if it was incongruent (e.g., mat). In Experiments 3 and 4, performance was better for targets with more preexisting congruent neighbors than for targets with more preexisting incongruent neighbors. These results demonstrate that orthographic similarity effects in semantic categorization are conditional on semantic congruency. This strongly suggests that semantic information becomes available before orthographic processing has been completed.     

Differential induction of c-Jun and Fos-like proteins in rat hippocampus and dorsal striatum after training in two water maze tasks

Research examining the neuroanatomical bases of memory in mammals suggests that the hippocampus and dorsal striatum are parts of independent memory systems that mediate "cognitive" and stimulus-response "habit" memory, respectively. At the molecular level, increasing evidence indicates a role for immediate early gene (IEG) expression in memory formation. The present experiment examined whether acquisition of cognitive and habit memory result in differential patterns of IEG protein product expression in these two brain structures. Adult male Long-Evans rats were trained in either a hippocampal-dependent spatial water maze task, or a dorsal striatal-dependent cued water maze task. Ninety minutes after task acquisition, brains were removed and processed for immunocytochemical procedures, and the number of cells expressing Fos-like immunoreactivity (Fos-like-IR) and c-Jun-IR in sections from the dorsal hippocampus and the dorsal striatum were counted. In the dorsal hippocampus of rats trained in the spatial task, there were significantly more c-Jun-IR pyramidal cells in the CA1 and CA3 regions, relative to rats that had acquired the cued task, yoked controls (free-swim), or na?ve (home cage) rats. Relative to rats receiving cued task training and control conditions, increases in Fos-like IR were also observed in the CA1 region of rats trained in the spatial task. In rats that had acquired the cued task, patches of c-Jun-IR were observed in the posteroventral striatum; no such patches were evident in rats trained in the spatial task, yoked-control rats, or na?ve rats. The results demonstrate that IEG protein product expression is up-regulated in a task-dependent and brain structure-specific manner shortly after acquisition of cognitive and habit memory tasks.     

Symmetry perception in humans and macaques

The human ability to detect symmetry has been a topic of interest to psychologists and philosophers since the 19th century, yet surprisingly little is known about the neural basis of symmetry perception. In a recent fMRI study, Sasaki and colleagues begin to remedy this situation. By identifying the neural structures that respond to symmetry in both humans and macaques, the authors lay the groundwork for understanding the neural mechanisms underlying symmetry perception.