Eye blink rate predicts reward decisions in adolescents

The ventral striatum displays hyper‐responsiveness to reward in adolescents relative to other age groups, and animal research on the developmental trajectory of the dopaminergic system suggests that dopamine may underlie adolescent sensitivity to reward. However, practical limitations prevent the direct measurement of dopamine in healthy adolescents. Eye blink rate (EBR) shows promise as a proxy measure of striatal dopamine D2 receptor function. We investigated developmental differences in the relationship between EBR and reward‐seeking behavior on a risky decision‐making task. Increasing EBR was associated with greater reward maximization on the task for adolescent but not adult participants. Furthermore, adolescents demonstrated greater sensitivity to reward value than adults, as evinced by shifts in decision patterns based on increasing potential reward. These findings suggest that previously observed adolescent behavioral and neural hypersensitivity to reward may in fact be due to greater dopamine receptor activity, as represented by the relationship of blink rate and reward‐seeking behavior. They also demonstrate the feasibility and utility of using EBR as a proxy for dopamine in healthy youth in whom direct measurements of dopamine are prohibitively invasive.     

The influence of lying positions and postural control on hand-mouth and hand-hand behaviors in 0-4-month-old infants

The purpose of this study was to verify how and when body position and postural control affect hand-mouth and hand-hand behaviors in infants during their first 4 months of life. Forty healthy infants were positioned in supine, prone and side-lying positions so that frequency and duration of the behaviors were quantified. Postural control when in supine and prone was also analyzed. The prone position elicited hand-mouth behavior in 0-2-month-old infants. The side-lying position elicited hand-mouth behavior in 3-4-month-old infants and hand-hand behavior in 2-4-month-olds. The increased postural control promoted the emergence of hand-hand behavior when in supine, and decreased hand-mouth behavior when in prone. The results show that self-exploratory behaviors may be affected not only by extrinsic constraints, represented by different body positions, but also by intrinsic constraints, represented by characteristic action possibilities and postural control of each age group.     

Memory abilities in Williams syndrome: Dissociation or developmental delay hypothesis?

Williams syndrome (WS) is a neurodevelopmental genetic disorder often described as being characterized by a dissociative cognitive architecture, in which profound impairments of visuo-spatial cognition contrast with relative preservation of linguistic, face recognition and auditory short-memory abilities. This asymmetric and dissociative cognition has been also proposed to characterize WS memory ability, with sparing of auditory short-term memory and impairment of spatial and long-term memory abilities. In this study, we explored the possibility of a double memory dissociation in WS (short- versus long-term memory; verbal versus visual memory). Thus, verbal memory abilities were assessed using California Verbal Learning Test and Digit Span and Rey-Osterrieth Complex Figure and Corsi Blocks was used to assess visual-spatial memory abilities. Overall, WS subjects were found to present a generalized significant impairment in verbal and visuo-spatial components either in short- or long-term memory. In sum, data from this study brings support for a developmental delay hypothesis, rather than a double dissociation within memory systems in WS.     

Behavioral and fMRI evidence that cognitive ability modulates the effect of semantic context on speech intelligibility

Text cues facilitate the perception of spoken sentences to which they are semantically related (Zekveld, Rudner, et al., 2011). In this study, semantically related and unrelated cues preceding sentences evoked more activation in middle temporal gyrus (MTG) and inferior frontal gyrus (IFG) than nonword cues, regardless of acoustic quality (speech in noise or speech in quiet). Larger verbal working memory (WM) capacity (reading span) was associated with greater intelligibility benefit obtained from related cues, with less speech-related activation in the left superior temporal gyrus and left anterior IFG, and with more activation in right medial frontal cortex for related versus unrelated cues. Better ability to comprehend masked text was associated with greater ability to disregard unrelated cues, and with more activation in left angular gyrus (AG). We conclude that individual differences in cognitive abilities are related to activation in a speech-sensitive network including left MTG, IFG and AG during cued speech perception.     

Temporal factors in pattern vision

A sequence of uncorrelated randomly patterned visual stimuli (“visual noise”) is normally seen as a field of particles in “Brownian motion.” When each frame of the sequence is followed by a blank flash superimposed on the same region of the visual field, the apparent structure of the noise field is strikingly altered, its form varying with the time interval between frame and flash. At a critical interval, many dots seem to cohere, to form maggot-like objects.

Some of the factors determining this critical interval have been studied. They include the brightness, repetition frequency and exposure duration of the noise field, and the distance of its retinal image from the fovea.

The critical interval for “perceptual blanking” is quite different from that for the “maggot effect,” but the two show a suggestively similar dependence upon the duty cycle of the noise display.

It is of some neurological interest that the phenomenon is not appreciably visible with dichoptic mixing of noise and blank stimuli.     

Effects of Visual Manipulation in Sit-to-Stand Movement in Children With Cerebral Palsy

The authors sought to verify the effects of vision on sit-to-stand (STS) movement performance by means of postural sway in children with cerebral palsy (CP) and typical children (TC). Participants were 42 TC and 21 children with CP. STS movement was assessed with eyes open and with eyes closed. Area and velocity of center of pressure sway were analyzed in each of the 3 STS phases. We observed greater postural sway during STS movement with eyes closed. Children with CP presented greater postural sway than TC did. Both groups exhibited greater postural instability with absence of vision expressing the role of vision to keep postural stability. Moreover, the greater postural instability was observed in children with CP.     

Symbouki: a meta‐analysis on the emergence of sound symbolism in early language acquisition

Adults and toddlers systematically associate pseudowords such as “bouba” and “kiki” with round and spiky shapes, respectively, a sound symbolic phenomenon known as the “bouba‐kiki effect”. To date, whether this sound symbolic effect is a property of the infant brain present at birth or is a learned aspect of language perception remains unknown. Yet, solving this question is fundamental for our understanding of early language acquisition. Indeed, an early sensitivity to such sound symbolic associations could provide a powerful mechanism for language learning, playing a bootstrapping role in the establishment of novel sound–meaning associations. The aim of the present meta‐analysis (SymBouKi) is to provide a quantitative overview of the emergence of the bouba‐kiki effect in infancy and early childhood. It allows a high‐powered assessment of the true sound symbolic effect size by pooling over the entire set of 11 extant studies (six published, five unpublished), entailing data from 425 participants between 4 and 38 months of age. The quantitative data provide statistical support for a moderate, but significant, sound symbolic effect. Further analysis found a greater sensitivity to sound symbolism for bouba‐type pseudowords (i.e., round sound‐shape correspondences) than for kiki‐type pseudowords (i.e., spiky sound‐shape correspondences). For the kiki‐type pseudowords, the effect emerged with age. Such discrepancy challenges the view that sensitivity to sound symbolism is an innate language mechanism rooted in an exuberant interconnected brain. We propose alternative hypotheses where both innate and learned mechanisms are at play in the emergence of sensitivity to sound symbolic relationships.     

Upward and Downward Counterfactual Thought After Loss: A Multiwave Controlled Longitudinal Study

Counterfactual thoughts, mental simulations about how a situation may have turned out differently (i.e., “if only …, then …”), can reduce mental health after stressful life-events. However, how specific counterfactual thought types relate to post-loss mental health problems is unclear. We hypothesized that self-referenced upward counterfactuals (i.e., “If only I had done …, then the current situation would be better”) may serve as cognitive avoidance, thereby perpetuating loss-related distress. Conversely, downward counterfactuals (i.e., “If … had happened, then the current situation could have been [even] worse”) may facilitate benefit finding, thereby reducing distress. In a longitudinal survey, self-referent, other-referent, and nonreferent upward counterfactuals, and nonreferent downward counterfactuals were assessed at baseline. Prolonged grief and depression symptoms were assessed at baseline, and 6- and 12-month follow-ups. Multiple regression analyses assessed associations between counterfactual thoughts and symptom levels in 65 recently bereaved people who generated counterfactual thoughts about the loss-event. Moderator analyses assessed the unicity of significant effects in the previous step, by comparing these effects in 59 people generating loss-related counterfactuals with those in 59 propensity-score matched participants generating counterfactuals about other negative life-events. Multivariate analyses showed that nonreferent upward counterfactuals were uniquely strongly positively associated with prolonged grief and depression symptoms concurrently. Self-referent upward counterfactuals were uniquely positively associated with prolonged grief and depression symptoms longitudinally. Moderator analyses confirmed that thinking about how one’s (in)actions could prevent a death uniquely exacerbated prolonged grief and depression severity. Prolonged grief treatment may be improved by targeting self-blame and guilt.     

Auditory–Visual stimuli: Effects on derived relations with compound stimuli

This research explored the effect of teaching conditional discriminations with three procedures on the derivation of 36 stimuli relations (derived relations). The stimuli used consisted of three characteristics musical instruments, along with the corresponding picture. In the first experiment six university students were trained with simple stimuli and tested with compound auditory–visual samples; therefore, a one‐to‐many structure was used. In the second experiment, auditory stimuli were replaced by visual stimuli, for the samples used, for new students. A third experiment was implemented with an extra phase of training with compound stimuli for six new students. The structure of the experiments was: pretests (Xbcd–A; Xacd–B; Xabd–C; Xabc–D), training (A–B; A–C; A–D), and posttests (same as pretests). The difference between these conditions was the kind of stimuli used and a new phase of teaching used in condition 3: (Xbcd–A). The results indicate that training with simple stimuli on discriminations that include stimuli that are easy to discriminate from each other (words and sounds) is a sufficient condition for good posttest performance. However, when comparisons are made difficult (words only), participants show better performance on new tests if they have a learning history with compound stimuli.     

Affect in Play Scale-Preschool Version: Validation on a Sample of School Age Italian Children

The Affect in Play Scale-Preschool version is a semi-structured measure of cognitive and affective pretend play processes using a 5?min standardized play task devised for preschool children. This study investigated an extension of the scale in a sample of 333 children, aged 6–10 years. Participants were assessed using another measure of play processes, the Affect in Play Scale, a divergent thinking task, the Alternate Uses Test, a measure of school coping, the School Coping measure, and a measure of empathy, the Index of Empathy for Children. External validity with these measures was investigated, using correlational analyses. Construct validity of the scale was assessed using a confirmatory factor analysis approach. A correlated two-factor structure with a cognitive and an affective factor demonstrated the best fit. Implications for the use of this extension to assess cognitive and affective processes in pretend play and developmental outcomes were discussed.