The effects of environmental support and secondary tasks on visuospatial working memory

In the present experiments, we examined the effects of environmental support on participants’ ability to rehearse locations and the role of such support in the effects of secondary tasks on memory span. In Experiment 1, the duration of interitem intervals and the presence of environmental support for visuospatial rehearsal (i.e., the array of possible memory locations) during the interitem intervals were both manipulated across four tasks. When support was provided, memory spans increased as the interitem interval durations increased, consistent with the hypothesis that environmental support facilitates rehearsal. In contrast, when environmental support was not provided, spans decreased as the duration of the interitem intervals increased, consistent with the hypothesis that visuospatial memory representations decay when rehearsal is impeded. In Experiment 2, the ratio of interitem interval duration to intertrial interval duration was kept the same on all four tasks, in order to hold temporal distinctiveness constant, yet forgetting was still observed in the absence of environmental support, consistent with the decay hypothesis. In Experiment 3, the effects of impeding rehearsal were compared to the effects of verbal and visuospatial secondary processing tasks. Forgetting of locations was greater when presentation of to-be-remembered locations alternated with the performance of a secondary task than when rehearsal was impeded by the absence of environmental support. The greatest forgetting occurred when a secondary task required the processing visuospatial information, suggesting that in addition to decay, both domain-specific and domain-general effects contribute to forgetting on visuospatial working memory tasks.     

Influence of emotional valence and arousal on the spread of activation in memory

Controversy still persists on whether emotional valence and arousal influence cognitive activities. Our study sought to compare how these two factors foster the spread of activation within the semantic network. In a lexical decision task, prime words were varied depending on the valence (pleasant or unpleasant) or on the level of emotional arousal (high or low). Target words were carefully selected to avoid semantic priming effects, as well as to avoid arousing specific emotions (neutral). Three SOA durations (220, 420 and 720 ms) were applied across three independent groups. Results indicate that at 220 ms, the effect of arousal is significantly higher than the effect of valence in facilitating spreading activation while at 420 ms, the effect of valence is significantly higher than the effect of arousal in facilitating spreading activation. These findings suggest that affect is a sequential process involving the successive intervention of arousal and valence.     

A model‐based approach to limb apraxia in Alzheimer's disease

Limb apraxia is a neurological deficit characterized by an inability to pantomime and/or imitate gestures, which can result from neurodegenerative disorders such as Alzheimer's disease (AD). The major goal of the study was to describe comprehensively the apraxia deficits observed in AD patients and to relate those deficits to general cognitive status, measures of daily activity, and other neuropsychological measures. Limb apraxia was assessed on a variety of conceptual and gesture production tasks in 30 AD patients. As a group, AD patients were impaired across gesture production tasks: of note was the greater impairment in imitation, as opposed to pantomime, which was especially pronounced when patients were imitating with a delay. Imitation performance was best predicted by measures of visuospatial processing, while imitation with delay was best predicted by measures of working memory. In addition, pantomime in response to pictures of tools was less accurate than Pantomime to Verbal Command and holding the tool during performance did not decrease the participants' impairment, while introducing a verbal cue during imitation increased the severity of deficits. Furthermore, investigation into patterns of deficits clearly demonstrated that the nature of limb apraxia deficits observed in AD can be quite heterogeneous and that dissociations between the conceptual and the production system exist. Finally, we also report on significant correlations between general cognitive status and limb apraxia.     

Quantity discrimination by kittens of the domestic cat (Felis silvestris catus)

Animal Cognition - Quantitative abilities are well described in many species and in diverse life situations, including in the adult domestic cat. However, such abilities have been much less studied...     

Social isolation, psychological health, and protective factors in adolescence

This study investigates the relationships among social isolation, psychological health, and protective factors in adolescents. Feelings of social isolation may influence psychological health in adolescents, but protective factors such as family connectedness, school connectedness, and academic achievement may also play a key role. The sample included 4,746 adolescents from 31 middle and high schools. Participants responded to 221 survey questions regarding peer relationships, psychological health, school connectedness, family relationships, and academic achievement. The findings revealed that social isolation was associated with an increased risk for depressive symptoms, suicide attempts, and low self-esteem. Protective factors influenced associations between social isolation and psychological health. Implications for prevention such as building healthy peer relationships, promoting family connectedness, and developing school-based interventions are discussed.     

The ABCs of CBT (Cognitive Behavior Therapy): Evidence‐Based Approaches to Child Anxiety in Public School Settings

This study evaluated a locally developed cognitive behavior therapy (CBT) intervention program in a public elementary school. In the prevention approach, 118 children were randomly assigned either to an 8‐week intervention or to a waitlist control. Results of statistical analysis indicated that the manualized CBT intervention did not reduce symptoms of anxiety on either self‐reports or parent reports of anxiety symptoms in the general school population. Challenges to translational efforts to public school settings are discussed.     

The update of semantic memories in amnestic mild cognitive impairment

It is still controversial to what extent neocortical consolidated memories are susceptible of change by processes of reconsolidation and transformation throughout experience, and whether the medial temporal lobes are necessary for this update of semantic consolidated memories, as they are for episodic remembering. We hypothesize that patients with amnestic mild cognitive impairment (aMCI) who have deficits in episodic memory may also have difficulties in updating information on added new features of objects. Sixteen participants with aMCI and 20 healthy control participants performed a semantic word-to-picture task, in which they were asked to identify as belonging to a given semantic category NEW objects, that have incorporated novel features, as well as OLD items, semantically and visually SIMILAR items and UNRELATED items. Patients with aMCI made a greater percentage of errors than healthy controls. Participants globally made greater percentages of errors in difficult types of items, namely NEW and SIMILAR, as compared to easier ones, OLD and UNRELATED. Importantly, an item by diagnostic group interaction effect was observed, and post hoc analysis showed that patients with aMCI made a higher percentage of errors than controls in NEW items only. In conclusion, patients with aMCI had a particular difficulty in identifying the NEW items of the word-to-picture task as compared to the control participants, supporting the concept of a flexible and dynamic conceptual knowledge system, involving the update of semantic memories and the integration of new attributes in a constant transformation process, which is impaired in these patients.     

Holistic processing of faces is intact in adults with autism spectrum disorder

Are face recognition difficulties in Autism Spectrum Disorders (ASD) related to impaired holistic processing? Gauthier et al. [Gauthier, I., Klaiman, C., &; Schultz, R. T. (2009). Face composite effects reveal abnormal face processing in Autism spectrum disorders. Vision Research, 49, 470–478. doi:10.1016/j.visres.2008.12.007] used the face composite task in adolescents with autism and found a congruency effect that was not modulated by alignment, a result which was interpreted as reflecting qualitatively different face processing mechanisms. In the present study we tested adults with ASD in a composite face task where presentation times were manipulated and further explored whether these participants were sensitive to holistic information in faces using a new version of the composite task: VHFPT 2.0 (The Vanderbilt Holistic Face Processing Test 2.0). Results suggest that adults with ASD process faces holistically and that their facial identity processing abilities are qualitatively similar and as efficient as that of typical adults. The difference between the results of Gauthier et al. (2009) with adolescents and the results with adults here reported are interpreted in terms of a developmental delay.