Fragile X syndrome is a neurodevelopmental disorder that is caused by large methylated expansions of a CGG repeat (>200) region upstream of the FMR1 gene that results in the lack of expression of the fragile X mental retardation protein (FMRP). Affected individuals display a neurobehavioral phenotype that includes a significant impairment in…

Performance on a covert visual attention task is compared between a group of adults with developmental dyslexia (specifically phonological difficulties) and a group of age and IQ matched controls. The group with dyslexia were generally slower to detect validly-cued targets. Costs of shifting attention toward the periphery when the target was…

The goal of the present investigation was to explore the possible expression of hemispheric-specific processing during the planning and execution of a bimanual reaching task. Participants (N=9) completed 80 bimanual reaching movements (requiring simultaneous, bilateral production of arm movements) to peripherally presented targets while…

In the present study, a cross-modal semantic priming task was used to investigate the ability of left-hemisphere-damaged (LHD) nonfluent aphasic, right-hemisphere-damaged (RHD) and non-brain-damaged (NBD) control subjects to use a discourse context to resolve lexically ambiguous words. Subjects first heard four-sentence discourse passages ending…

The purpose of the current investigation was to examine the age-related changes in the performance of the two hands on the Annett pegboard (Annett, 1970). The current study was part of a large-scale study investigating the development of unimanual and bimanual performance. Three hundred and two right-handed individuals participated in the present…

According to Annett (1985), pronounced left hemisphere lateralization for language abilities in women, as in female absolute right-handers, limits their right hemisphere capacity and spatial abilities. This study examines the degree of handedness and the family history of non-right-handedness with respect to real-life spatial abilities in women.…

Semantic and syntactic contributions to processing of mass and count nouns were assessed by examining the performance of a patient suffering from a pure semantic deficit. Semantic and syntactic processing was evaluated on grammaticality judgement and sentence-picture matching tasks, respectively, where each task involved mass and count readings of…

Neglect patients typically show motor perseveration while canceling targets on the ipsilesional side. This behavior can be influenced by the presence vs. absence of targets on the (neglected) contralesional side (Bottini & Toraldo, 2003). As alternative explanations, the authors proposed (i) directional hypokinesia-the patient cannot perform…

This study examined the effect of transformed visual feedback on movement control in Huntington's disease (HD). Patients in the early stages of HD and controls performed aiming movements towards peripheral targets on a digitizing tablet and emphasizing precision. In a baseline condition, HD patients were slower but showed few precision problems in…

The role of emotion in complex decision-making can be assessed on the Iowa Gambling Task (IGT), a widely used neuropsychological measure that may tap a different aspect of executive function than that assessed by conventional measures. Most notably, the 'feeling' about which decks are good or bad, often described in relation to IGT performance,…

Evidence suggests that perceptual networks in the ventral visual pathway are necessary for action control when targets are viewed with only one eye, or when the target must be stored in memory. We tested whether memory-linked (i.e., open-loop versus memory-guided actions) and monocular-linked effects (i.e., binocular versus monocular actions) on…

The nature of object representation in working memory is vital to establishing the capacity of working memory, which in turn shapes the limits of visual cognition and awareness. Although current theories discuss whether representations in working memory are feature-based or object-based, no theory has considered the role of past experience.…

Symmetry is an important concept in biology, being related to mate selection strategies, health, and survival of species. In human faces, the relevance of left-right symmetry to attractiveness and health is not well understood. We compared the appearance of facial attractiveness, health, and symmetry in three separate experiments. Participants…

Studies examining a relationship between attention deficit hyperactivity disorder (ADHD) and relative visual inattention towards left space have produced inconsistent results. Here, based on previous studies with adult neurological patients who show very severe inattention to the left, we examine whether any spatial bias in ADHD may be modulated…

Visual line bisection was investigated in 26 sinistral and 24 dextral subjects as a function of hemispace, hand and scan direction. An ANOVA revealed significant main effects for hand preference, due to the mean bisection errors of dextral subjects being significantly leftward of those of sinistral subjects; for hand, due to the bisection errors…