Generalized relational matching by guinea baboons (Papio papio) in two-by-two-item analogy problems

Analogical reasoning is considered the hallmark of human reasoning, but some studies have demonstrated that language- and symbol-trained chimpanzees can also reason analogically. Despite the potential adaptive value of this ability, evidence from other studies strongly suggests that other nonhuman primates do not have this capacity for analogical reasoning. In our three experiments, 6 of 29 baboons acquired the ability to perform a relational matching-to-sample (RMTS) task in which pairs of shapes composed relational displays. Five of these 6 monkeys then transferred this ability to RMTS tasks using novel exemplars of identity (elements in a pair are the same) and nonidentity (elements in a pair are different) relations. This transfer occurred even on trials in which the incorrect pair shared an element with the sample pair with which it was being compared. The baboons retained this ability 12 months later. The findings from our study of symbol-naive monkeys indicate that although language and symbol training facilitate conceptual thinking in nonhuman primates, such training is not a prerequisite for analogical reasoning.     

Self‐esteem,perception of relationships,and emotional distress: A cross‐cultural study

This study examined the relative importance of self‐esteem, family cohesion, and support from friends in predicting depressed mood and anxiety in Japanese and American college students. Contrary to expectations, self‐esteem was the strongest predictor of emotional distress in both groups of students. Nevertheless, consistent with predictions derived from Markus and Kitayama's theory of self‐construals, family cohesion accounted for a significantly larger percentage of the variance in predicting emotional distress in Japan than in the United States. In both countries, the relations between support from friends and the measures of emotional distress were entirely mediated by self‐esteem. However, among Japanese students, family cohesion accounted for additional significant variance in predicting the measures of emotional distress, even after controlling for self‐esteem.     

Differential effects of emotional arousal in short- and long-term memory in healthy adults

Recent studies demonstrated important differences between short- and long-term memory mechanisms. Besides, the emotional component has a crucial role in memory formation. This study was carried out to answer whether there is a differential influence of emotional arousal in short- and long-term memory in healthy adults. Thirty-one healthy volunteers were divided into two major groups. In the first group long-term memory (LTM) was evaluated, with the testing session one week after training. The second group was tested 1h after training, where short-term memory (STM) was evaluated. Each group was divided in to two subgroups. One half of the volunteers was exposed to an emotionally neutral story, and the other half of each group was exposed to a closely matched but more emotionally arousing story. The testing session consisted of a questionary containing 80 questions of multiple choices. The results were evaluated through percentage of correct answers. Results showed that correct answers were increased, in LTM measures, in the subjects that were given the emotional version of the test. In STM measures, no differences were found between the emotional and neutral version. However, the presentation of emotional story caused an emotional reaction in both groups. The lack of effect of emotional arousal in STM suggests that amygdala is not related to STM mechanisms. Further studies using different approaches are needed to elucidate if STM processes are influenced by emotional arousal.     

Mother still knows best: Maternal influence uniquely modulates adolescent reward sensitivity during risk taking

Adolescent decision‐making is highly sensitive to input from the social environment. In particular, adult and maternal presence influence adolescents to make safer decisions when encountered with risky scenarios. However, it is currently unknown whether maternal presence confers a greater advantage than mere adult presence in buffering adolescent risk taking. In the current study, 23 adolescents completed a risk‐taking task during an fMRI scan in the presence of their mother and an unknown adult. Results reveal that maternal presence elicits greater activation in reward‐related neural circuits when making safe decisions but decreased activation following risky choices. Moreover, adolescents evidenced a more immature neural phenotype when making risky choices in the presence of an adult compared to mother, as evidenced by positive functional coupling between the ventral striatum and medial prefrontal cortex. Our results underscore the importance of maternal stimuli in bolstering adolescent decision‐making in risky scenarios.     

Effects of training condition on the contribution of specific items to relational processing in baboons (Papio papio)

Relational processing involves learning about the relationship between or among stimuli, transcending the individual stimuli, so that abstract knowledge generalizable to novel situations is acquired. Relational processing has been studied in animals as well as in humans, but little attention has been paid to the contribution of specific items to relational thinking or to the factors that may affect that contribution. This study assessed the intertwined effects of item and relational processing in nonhuman primates. Using a procedure that entailed both expanding and contracting sets of pictorial items, we trained 13 baboons on a two-alternative forced-choice task, in which they had to distinguish horizontal from vertical relational patterns. In Experiment 1, monkeys engaged in item-based processing with a small training set size, and they progressively engaged in relation-based processing as training set size was increased. However, in Experiment 2, overtraining with a small stimulus set promoted the processing of item-based information. These findings underscore similarities in how humans and nonhuman primates process higher-order stimulus relations.     

A sensorimotor account of vision and visual consciousness

Many current neurophysiological, psychophysical, and psychological approaches to vision rest on the idea that when we see, the brain produces an internal representation of the world. The activation of this internal representation is assumed to give rise to the experience of seeing. The problem with this kind of approach is that it leaves unexplained how the existence of such a detailed internal representation might produce visual consciousness. An alternative proposal is made here. We propose that seeing is a way of acting. It is a particular way of exploring the environment. Activity in internal representations does not generate the experience of seeing. The outside world serves as its own, external, representation. The experience of seeing occurs when the organism masters what we call the governing laws of sensorimotor contingency. The advantage of this approach is that it provides a natural and principled way of accounting for visual consciousness, and for the differences in the perceived quality of sensory experience in the different sensory modalities. Several lines of empirical evidence are brought forward in support of the theory, in particular: evidence from experiments in sensorimotor adaptation, visual "filling in," visual stability despite eye movements, change blindness, sensory substitution, and color perception.     

Transfer of newly acquired stimulus valence between identities in dissociative identity disorder (DID)

Patients with Dissociative Identity Disorder (DID) frequently report episodes of interidentity amnesia, that is amnesia for events experienced by other identities. The goal of the present experiment was to test the implicit transfer of trauma-related information between identities in DID. We hypothesized that whereas declarative information may transfer from one identity to another, the emotional connotation of the memory may be dissociated, especially in the case of negative, trauma-related emotional valence. An evaluative conditioning procedure was combined with an affective priming procedure, both performed by different identities. In the evaluative conditioning procedure, previously neutral stimuli come to refer to a negative or positive connotation. The affective priming procedure was used to test the transfer of this acquired valence to an identity reporting interidentity amnesia. Results indicated activation of stimulus valence in the affective priming task, that is transfer of emotional material between identities.