Role of vision and kinesthesis in location and distance estimates

Three experiments were conducted to investigate the visual/kinesthetic coding characteristics of two movement informations, i.e., location and distance. The first experiments used matching task procedures, the second experiment used visual augmentation and reduction procedures and the third experiment made use of an ischemic nerve block procedure. The findings' of the first experiment indicated a clear kinesthetic coding for distance information. Results suggest a kinesthetic coding for location cue, with the presence of vision (alone) on both phases of movements improving its accuracy. The second experiment ruled out a visual coding of distance cue and indicated a kinesthetic representation of location cue. Again, simultaneous presence of vision (only at the time of criterion movement) enhanced its performance. The third experiment confirmed a kinesthetic signalling of distance cue. Location cue, in conditions of the third experiment did not get influenced. Probably, muscle receptors in relation with central commands can handle location information. A multiple coding for location information is suggested.     

Associations between symptoms of maternal postpartum depression,gestational age and infant social withdrawal: A longitudinal study in a community cohort

Infant social withdrawal is a risk factor for non-optimal child development; thus, it is important to identify risk factors associated with withdrawal. In a large community sample (N = 19,017), we investigate whether symptoms of maternal and partner postpartum depression (PPD; measured with the Edinburgh Postnatal Depression Scale) and prematurity are predictors of infant social withdrawal (measured with the Alarm Distress Baby Scale). Withdrawal was assessed at 2–3, 4–7 and 8–12 months postpartum. Linear regressions showed that prematurity predicted higher infant social withdrawal at all time points, and maternal symptoms of PPD were positively associated with withdrawal at 2–3 months. Logistic regressions showed that odds for elevated social withdrawal were increased with elevated levels of maternal symptoms of PPD at 2–3 and 8–12 months. Partner's symptoms of PPD were not associated with withdrawal. Future studies should investigate how PPD symptoms and prematurity may impact the individual development of social withdrawal.     

Decision deadlines and uncertainty monitoring: the effect of time constraints on uncertainty and perceptual responses

The behavioral uncertainty response has grounded the study of animal metacognition and influenced the study of human psychophysics. However, the interpretation of this response is debated—especially whether it is a behavioral index of metacognition. The authors advanced this interpretation using the dissociative technique of response deadlines. Uncertainty responding, if it is higher level or metacognitive, should depend on a slower, more controlled decisional process and be more vulnerable to time constraints. Humans performed sparse–uncertain–dense or sparse–middle–dense discriminations in which, respectively, they could decline difficult trials or positively identify middle stimuli. Uncertainty responses were sharply and selectively reduced under a decision deadline, as compared to primary perceptual responses (i.e., “sparse,” “middle,” and “dense” responses). This dissociation suggests that the uncertainty response does reflect a higher-level, decisional response. It grants the uncertainty response a distinctive psychological role in its task and encourages an interpretation of this response as an elemental behavioral index of uncertainty that deserves continuing research.     

Differences in eye-movement patterns between anorexic and control observers when judging body size and attractiveness

Attentional biases may influence the eye-movements made when judging bodies and so alter the visual information sampled when making a judgment. This may lead to an overestimation of body size. We measured the eye-movements made by 16 anorexic observers and 16 age-matched controls when judging body size and attractiveness. We combined behavioural data with a novel eye-movement analysis technique that allowed us to apply spatial statistical techniques to make fine spatial discriminations in the pattern of eye-movements between our observer groups. Our behavioural results show that anorexic observers overestimate body size relative to controls and find bodies with lower body mass indexes more attractive. For both judgments, the controls' fixations centre on the stomach, but the anorexic observers show a much wider fixation pattern extending to encompass additional features such as the prominence of the hip and collar bones. This additional visual information may serve to alter their behavioural judgments towards an overestimation of body size and shift their ideal body size towards a significantly lower value.