Age-of-actor effect in body expression recognition of children

Investigations of developmental trajectories for emotion recognition suggest that both face- and body expression recognition increases rapidly in early childhood and reaches adult levels of performance near the age of ten. So far, little is known about whether children's ability to recognise body expressions is influenced by the age of the person they are observing. This question is investigated here by presenting 119 children and 42 young adults with videos of children, young adults and older adults expressing emotions with their whole body. The results revealed an own-age advantage for children, reflected in adult-level accuracy for videos of children for most expressions but reduced accuracy for videos of older adults. Children's recognition of older adults' expressions was not correlated with children's estimated amount of contact with older adults. Support for potential influences of social biases on performance measures was minimal. The own-age advantage was explained in terms of children's reduced familiarity with body expressions of older adults due to aging related changes in the kine�matics characteristics of movements and potentially due to stronger embodiment of other children's bodily movements

Influence of hand position on the near-effect in 3D attention

Voluntary reorienting of attention in real depth situations is characterized by an attentional bias to locations near the viewer once attention is deployed to a spatially cued object in depth. Previously this effect (initially referred to as the ‘near-effect’) was attributed to access of a 3D viewer-centred spatial representation for guiding attention in 3D space. The aim of this study was to investigate whether the near-bias could have been associated with the position of the response-hand, always near the viewer in previous studies investigating endogenous attentional shifts in real depth. In Experiment 1, the response-hand was placed at either the near or far target depth in a depth cueing task. Placing the response-hand at the far target depth abolished the near-effect, but failed to bias spatial attention to the far location. Experiment 2 showed that the response-hand effect was not modulated by the presence of an additional passive hand, whereas Experiment 3 confirmed that attentional prioritization of the passive hand was not masked by the influence of the responding hand on spatial attention in Experiment 2. The pattern of results is most consistent with the idea that response preparation can modulate spatial attention within a 3D viewer-centred spatial representation

Facial expression training optimises viewing strategy in children and adults

This study investigated whether training-related improvements in facial expression categorization are facilitated by spontaneous changes in gaze behaviour in adults and nine-year old children. Four sessions of a self-paced, free-viewing training task required participants to categorize happy, sad and fear expressions with varying intensities. No instructions about eye movements were given. Eye-movements were recorded in the first and fourth training session. New faces were introduced in session four to establish transfer-effects of learning. Adults focused most on the eyes in all sessions and increased expression categorization accuracy after training coincided with a strengthening of this eye-bias in gaze allocation. In children, training-related behavioural improvements coincided with an overall shift in gaze-focus towards the eyes (resulting in more adult-like gaze-distributions) and towards the mouth for happy faces in the second fixation. Gaze-distributions were not influenced by the expression intensity or by the introduction of new faces. It was proposed that training enhanced the use of a uniform, predominantly eyes-biased, gaze strategy in children in order to optimise extraction of relevant cues for discrimination between subtle facial expressions

Advance preparation of set-switches in Parkinson’s disease

Eighteen patients with Parkinson’s disease (PD) and 18 healthy control subjects were presented with a switching task where stimuli elicited either one (no-conflict condition) or two (conflict condition) task-relevant stimulus-response mappings. The response stimulus interval (RSI) between trials was varied to allow investigation of the extent to which participants engaged in advanced preparation of task set. In line with previous findings, set-switching deficits of PD patients were only observed in the conflict condition. Prolonging the RSI led to a reduction of switch costs for control subjects in both the conflict and the no-conflict task, whereas this effect was attenuated for PD patients in the conflict condition. This deficit was explained in terms of a reduced ability to maintain cue-action representations active in working memory in high interference conditions, and was related to the possible role of the frontostriatal circuit in maintaining focussed attention

Voluntary and automatic visual spatial shifts of attention in Parkinson's disease: an analysis of costs and benefits

Visual spatial shifts of attention were investigated in 13 patients suffering from Parkinson's disease and 20 control subjects. Attention was directed towards a target location with peripheral or central cues at varying SOAs in two separate experiments. A benefit and cost analysis was conducted on reaction times. The results of the central cueing task showed that in comparison with control subjects, costs of invalid cueing were reduced in patients. Results of the peripheral cueing task revealed that although the cueing effect (validin valid) was similar for patients and controls, the effect of valid cueing (neutral valid) was greater in patients. The effects observed in both tasks were explained as an impaired ability of patients with Parkinsons disease to maintain attention

Reduced task-set inertia in Parkinson's disease

This study investigated the relationship between cognitive inhibition and set-switching costs in 13 patients with Parkinson's disease (PD) and 16 control subjects using a set-switching task with fully predictable switches. Incongruent colour-words and numerals were presented in either baseline (only colour-words or only numerals) or alternating lists (colour-words and numerals in alternation). Words required either a word-reading or colour-naming response whereas numerals required either a value-naming (value of the digits) or group-size naming (number of digits) response. Stroop interference was found to be increased and practice effects on nondominant tasks reduced in PD patients, suggesting that the ability to increase control over interference from irrelevant prepotent responses may be implicated in PD. Switch costs of PD patients were reduced on the first few trials of alternating dominant task lists and increased towards the end of alternating nondominant task lists. Both effects were explained as resulting from a reduced ability to maintain task-sets where selection of correct responses relies on inhibition of irrelevant stimulus-response mappings

Average Proportions Viewing Time (second fixation only) as a function of Training session, ROI, Emotion and Age-group.

<p>Average Proportions Viewing Time (second fixation only) as a function of Training session, ROI, Emotion and Age-group.</p

ERP evidence for human early visual sensitivity to co-linearity compared to co-circularity

Our complex visual environment is constrained by natural geometric regularities, including spatiotem-poral regularity, co-linearity and co-circularity. To investigate human visual processing associated withthese regularities we directly compared the neural processes in encoding dynamic co-linearity and co-circularity using event-related potentials (ERPs). By recording ERPs to a target bar presented alone (nocontext) or in a dynamic sequence of bars following a co-linear or co-circular path, we observed earlierERPs to targets embedded in co-linear sequence at early (66 ms) and later stages (197 ms) of post-targetprocessing. In contrast, targets in co-circular sequence only modulated ERPs at later stages of processing.It is proposed that early visual processing may have adapted to efficiently process co-linearity to improvetarget identification, whereas sensitivity to co-circularity does not occur until later stages of processing.These results have significant impact for understanding brain-behaviour relationships when processingnatural geometric regularities

Total number of fixations made on average during face viewing (Nr Fix) as a function of Training and Emotion.

<p>Total number of fixations made on average during face viewing (Nr Fix) as a function of Training and Emotion.</p

Average Proportions Viewing Time (considering all fixations during face-viewing) as a function of Training session, ROI (Region of Interest), Emotion and Age-group.

<p>Average Proportions Viewing Time (considering all fixations during face-viewing) as a function of Training session, ROI (Region of Interest), Emotion and Age-group.</p