Are Reaching Movements Planned to be Straight and Invariant in the Extrinsic Space? Kinematic Comparison Between Compliant and Unconstrained Motions

Two main questions were addressed in the present study. First, does the existence of kinematic regularities in the extrinsic space represent a general rule? Second, can the existence of extrinsic regularities be related to specific experimental situations implying, for instance, the generation of compliant motion (i.e. a motion constrained by external contact)? To address these two questions we studied the spatio-temporal characteristics of unconstrained and compliant movements. Five major differences were observed between these two types of movement: (1) the movement latency and movement duration were significantly longer in the compliant than in the unconstrained condition; (2) whereas the hand path was curved and variable according to movement direction for the unconstrained movements, it was straight and invariant for the compliant movements; (3) whereas the movement end-point distribution was roughly circular for the unconstrained movements, it was consistently elongated and typically oriented in the movement direction for the compliant movements; (4) whereas constant errors varied as a function of target eccentricity for the unconstrained movements, they were independent of this factor for the compliant movements; (5) the instruction to move the final effector along a straight line path influenced the characteristics of the unconstrained movements but not the characteristics of the compliant movements. When considered together, the previous observations suggest that compliant and unconstrained movements involve different planning strategies. Our data support the hypothesis that unconstrained motions, unlike compliant motions, are not programmed to follow a straight line path in the extrinsic space. This observation provides a theoretical frame of reference within which some apparently contradictory results reported in the movement generation literature may be explained.     

Premise Misinterpretation and Syllogistic Reasoning

A study by Ceraso and Provitera (1971) found that elaboration of the premises used in syllogistic reasoning led to substantially improved performance. This finding is of considerable importance because of the implications it has for mental logic and mental models theories of reasoning. Three experiments are reported, which replicated and extended the original findings. It was found that elaboration led to a significant improvement in performance, but that this was confined to multiple model syllogisms, where the elaboration has the effect of reducing the number of models involved. A fourth experiment indicated that elaboration can vary within the same syllogism depending on the direction of the conclusion drawn. These findings are best explained under the assumption that reasoners build mental models when solving problems and that elaboration can reduce the number of possible models.     

Mothers’ attuned responses to infant affect expressivity promote earlier achievement of language milestones

To investigate infants’ affective expressivity and maternal attuned responsiveness to infant expressivity in relation to early language achievement, 77 dyads were visited in their homes at 9 and 13 months, and mothers were interviewed about their children’s language between 9 and 21 months. Maternal responses that were attuned to infant affect, by selectively matching either the gradient features or the valence of infants’ affective expressions, were more predictive of children’s language achievement than maternal nonmatching responses; and maternal matching responses at 9 months were more predictive of children’s language achievements than maternal responses at 13 months. Moreover, maternal matching responses at 9 months predicted second-year language achievements over and above infant affect expressivity at 9 and 13 months, and over and above maternal matching responses at 13 months. Infants’ affective expressivity per se was not predictive.     

The Relationship of Imperatives and Self-Efficacy to Indices of Social Anxiety

Seventy-three college students participated in a study to assess the role of self-efficacy and imperatives in social anxiety. The students were asked to speak in front of a small group of their peers and their anxiety and length of time talking were measured. Neither lower self-efficacy nor higher levels of imperative thinking at Baseline were correlated with higher levels of anxiety. The critical finding was that subjects who showed higher levels of imperative thinking at Baseline spoke for a significantly shorter period of time. This suggests that the participant's anxiety was moderated by the performance of an instrumental response, in this situation by choosing to limit the amount of time spent talking. The results suggest the centrality of imperative thinking in shaping behavior in the domain of social anxiety.     

Medical hermeneutics: Where is the “text” we are interpreting?

The present paper is a commentary on an article by Drew Leder [1]. Leder identifies a series of texts in the clinical encounter, emphasizes the central role of interpretation in making sense of each of these texts, and articulates ordering principles to guide the interpretive work.The metaphor of clinical work as textual explication, however, creates the expectation that there is a text somewhere to be found. Such an expectation invites doctors and patients to search for the text and runs the risk of conceptualizing patients as more static than they are. If one is to use the textual metaphor, one must appreciate the radical extent to which the clinical encounter is a mutually produced and shifting entity. The qualities of mutuality and indeterminacy are not those one usually associates with texts. One might ultimately be better served by a different metaphor based more directly on uncertainty.     

Seeing Is Believing: Using Video Feedback in Cognitive Therapy for Social Anxiety Disorder

Distorted negative self-images and impressions appear to play a key role in maintaining Social Anxiety Disorder (SAD). In previous research, McManus et al. (2009) found that video feedback can help people undergoing cognitive therapy for SAD (CT-SAD) to develop a more realistic impression of how they appear to others, and this was associated with significant improvement in their social anxiety. In this paper we first present new data from 47 patients that confirms the value of video feedback. Ninety-eighty percent of the patients indicated that they came across more favorably than they had predicted after viewing a video of their social interactions. Significant reductions in social anxiety were observed during the following week and these reductions were larger than those observed after control periods. Comparison with our earlier data (McManus et al., 2009) suggests we may have improved the effectiveness of video feedback by refining and developing our procedures over time. The second part of the paper outlines our current strategies for maximizing the impact of video feedback. The strategies have evolved in order to help patients with SAD overcome a range of processing biases that could otherwise make it difficult for them to spot discrepancies between their negative self-imagery and the way they appear on video.