The perception of briefly exposed point-sources of light

Point-sources of light (dots) were exposed for 10 to 50 msec, before five dark-adapted subjects in a dimly illuminated room. During voluntary fixation with one eye, the target was exposed some 10° on the nasal side of the optic axis. The intensity X duration of all targets was 2 X threshold and they consisted of either a single dot, or a pair of dots separated by a distance that was less than that required for two-point discrimination. In two-thirds of trials both the single-dot and the two-dot targets were perceived as short thin lines of various orientation. Although individual percepts were unpredictable, there was a preferred or most likely orientation for responses to the single-dot target; this was near to the horizontal for all five subjects. There was no significant difference between the preferred orientations for single-dot targets tested at sites more than 1° apart in the visual field. When two single-dot targets, separated by about 1°, were exposed simultaneously, the orientations of the perceived lines sometimes differed by as much as 80°; occasionally, one target was reported as a dot while the other was seen as a thin line. If the single-dot was briefly exposed between two continuously visible and parallel straight lines, the target usually appeared as a thin line, parallel to the framing lines. Some of these results appear to be consistent with the hypothesis that the human visual cortex, like that of the cat and monkey, contains neurones that are orientation specific.     

Improved Perceptions of Emotion Regulation and Reflective Functioning in Parents: Two Additional Positive Outcomes of Parent-Child Interaction Therapy

The purpose of this study was to test whether Parent-Child Interaction Therapy (PCIT), a widely used effective therapy for children’s externalizing behaviors and parenting problems, was associated with improvements in parents’ emotion regulation and reflective functioning. We also investigated whether these improvements had unique associations with children’s improvements in externalizing and internalizing symptoms. Participants were 139 Australian children aged 29 to 83 months and their caregivers; all were referred for child externalizing behavior problems coupled with parenting skill deficits or high parent stress. All data were gathered via a questionnaire completed prior to and after completion of PCIT. Significant improvements were found in parents’ self-reported emotion dysregulation and capacity to use cognitive reappraisal for emotion regulation. There was also improvement in parents’ self-report of children’s symptoms, parenting practices, and reflective functioning in the form of prementalizing, which measured a low capacity to understand the emotional world of the child. Multiple regression showed that improvements in cognitive reappraisal, prementalizing, and negative parenting practices were associated with improvement in children’s symptoms. The findings extend the existing evidence for PCIT as an effective parenting intervention, adding parents’ perceived emotion regulation and reflective functioning to the list of positive outcomes from PCIT. Improved emotion regulation and reflective functioning, unique from changes in parenting practices, could be mechanisms that help explain why PCIT has been associated with improvements in children’s externalizing behaviors.     

The City Infant Faces Database: A validated set of infant facial expressions

Adults need to be able to process infants’ emotional expressions accurately to respond appropriately and care for infants. However, research on processing of the emotional expressions of infant faces is hampered by the lack of validated stimuli. Although many sets of photographs of adult faces are available to researchers, there are no corresponding sets of photographs of infant faces. We therefore developed and validated a database of infant faces, which is available via e-mail request. Parents were recruited via social media and asked to send photographs of their infant (0–12 months of age) showing positive, negative, and neutral facial expressions. A total of 195 infant faces were obtained and validated. To validate the images, student midwives and nurses (n = 53) and members of the general public (n = 18) rated each image with respect to its facial expression, intensity of expression, clarity of expression, genuineness of expression, and valence. On the basis of these ratings, a total of 154 images with rating agreements of at least 75% were included in the final database. These comprise 60 photographs of positive infant faces, 54 photographs of negative infant faces, and 40 photographs of neutral infant faces. The images have high criterion validity and good test–retest reliability. This database is therefore a useful and valid tool for researchers.     

Young children with autism show atypical brain responses to fearful versus neutral facial expressions of emotion

Evidence suggests that autism is associated with impaired emotion perception, but it is unknown how early such impairments are evident. Furthermore, most studies that have assessed emotion perception in children with autism have required verbal responses, making results difficult to interpret. This study utilized high-density event-related potentials (ERPs) to investigate whether 3-4-year-old children with autism spectrum disorder (ASD) show differential brain activity to fear versus neutral facial expressions. It has been shown that normal infants as young as 7 months of age show differential brain responses to faces expressing different emotions. ERPs were recorded while children passively viewed photos of an unfamiliar woman posing a neutral and a prototypic fear expression. The sample consisted of 29 3-4-year-old children with ASD and 22 chronological age-matched children with typical development. Typically developing children exhibited a larger early negative component (N300) to the fear than to the neutral face. In contrast, children with ASD did not show the difference in amplitude of this early ERP component to the fear versus neutral face. For a later component, typically developing children exhibited a larger negative slow wave (NSW) to the fear than to the neutral face, whereas children with autism did not show a differential NSW to the two stimuli. In children with ASD, faster speed of early processing (i. e. N300 latency) of the fear face was associated with better performance on tasks assessing social attention (social orienting, joint attention and attention to distress). These data suggest that children with ASD, as young as 3 years of age, show a disordered pattern of neural responses to emotional stimuli.