Suchergebnisse

AbstractEye‐tracking paradigms are increasingly used to investigate higher‐level social and cognitive processing in autism spectrum disorder (ASD). However, the integrity of the oculomotor system within ASD is unclear, with contradictory reports of aberrant eye‐movements on basic oculomotor tasks. The purpose of the current study was to determine whether reducing population heterogeneity and distinguishing neurocognitive phenotypes can clarify discrepancies in oculomotor behaviour evident in previous reports. Reflexive and volitional eye‐movement control was assessed in 73 children aged 8–14 years from four distinct groups: Autism Language Normal (ALN), Autism Language Impaired (ALI), non‐autistic Language Impaired (LI) and Typically Developing (TD). Eye‐movement control was measured using pro‐ and antisaccade tasks and a novel 'search distracter' task to measure distractibility. Reflexive eye‐movements were equivalent across groups, but deficits in volitional eye‐movement control were found that aligned with language status, and were not specific to ASD. More than 80% of ALI and LI children presented error rates at least 1.5 SDs below the TD mean in an antisaccade task. In the search distracter task, 35.29% of ALI children and 43.75% of LI children had error rates greater than 1.5 SDs compared with 17.64% of ALN children. A significant proportion of children with neurodevelopmental disorders involving language function have pronounced difficulties suppressing reflexive saccades and maintaining fixations in the presence of competing stimuli. We extend the putative link between ALI and LI populations to non‐language tasks, and highlight the need to account for co‐morbidity in understanding the ontogenesis of ASD.

AbstractFacial expressions are one way in which infants and adults communicate emotion. Infants scan expressions similarly to adults, yet it remains unclear whether they are receptive to the affective information they convey. The current study investigates 6‐, 9‐ and 12‐month infants' (N = 146) pupillary responses to the six "basic" emotional expressions (happy, sad, surprise, fear, anger, and disgust). To do this we use dynamic stimuli and gaze‐contingent eye‐tracking to simulate brief interactive exchanges, alongside a static control condition. Infants' arousal responses were stronger for dynamic compared to static stimuli. And for dynamic stimuli we found that, compared to neutral, infants showed dilatory responses for happy and angry expressions only. Although previous work has shown infants can discriminate perceptually between facial expressions, our data suggest that sensitivity to the affective content of all six basic emotional expressions may not fully emerge until later in ontogeny.

AbstractInfants respond preferentially to faces and face‐like stimuli from birth, but past research has typically presented faces in isolation or amongst an artificial array of competing objects. In the current study infants aged 3‐ to 12‐months viewed a series of complex visual scenes; half of the scenes contained a person, the other half did not. Infants rapidly detected and oriented to faces in scenes even when they were not visually salient. Although a clear developmental improvement was observed in face detection and interest, all infants displayed sensitivity to the presence of a person in a scene, by displaying eye movements that differed quantifiably across a range of measures when viewing scenes that either did or did not contain a person. We argue that infant's face detection capabilities are ostensibly "better" with naturalistic stimuli and artificial array presentations used in previous studies have underestimated performance.

Abstract Human infants, just a few days of age, are known to prefer attractive human faces. We examined whether this preference is human‐specific. Three‐ to 4‐month‐olds preferred attractive over unattractive domestic and wild cat (tiger) faces (Experiments 1 and 3). The preference was not observed when the faces were inverted, suggesting that it did not arise from low‐level image differences (Experiments 2 and 3). In addition, the spontaneous preference for attractive tiger faces influenced performance in a recognition memory task involving attractive versus unattractive tiger face pairings (Experiment 4). The findings suggest that infant preference for attractive faces reflects the activity of general processing mechanisms rather than a specific adaptation to mate choice.

Abstract Adults are sensitive to the physical differences that define ethnic groups. However, the age at which we become sensitive to ethnic differences is currently unclear. Our study aimed to clarify this by testing newborns and young infants for sensitivity to ethnicity using a visual preference (VP) paradigm. While newborn infants demonstrated no spontaneous preference for faces from either their own‐ or other‐ethnic groups, 3‐month‐old infants demonstrated a significant preference for faces from their own‐ethnic group. These results suggest that preferential selectivity based on ethnic differences is not present in the first days of life, but is learned within the first 3 months of life. The findings imply that adults' perceptions of ethnic differences are learned and derived from differences in exposure to own‐ versus other‐race faces during early development.