One of the first concepts that students of neuroscience are exposed to is the overall organization of the nervous system and the two principle divisions of it: the Peripheral Nervous System (PNS) and the Central Nervous System (CNS). In sensory systems, this fundamental division plays a particularly prominent role in the information processing stream that integrates and processes information fr...

CLINICAL SCENARIO : Children with psychiatric disabilities such as Pervasive Development Disorder (PDD), Autism, Attention Deficit Hyperactivity Disorder (ADHD), and learning disabilities often have difficulties processing and interpreting sensory information. These difficulties may contribute to problems attending to schoolwork, behavioural problems or overall decreased productivity in a given...

Human reaction times during sensory-motor tasks vary considerably. To begin to understand how this variability arises, we examined neuronal populational response time variability at early versus late visual processing stages. The conventional view is that precise temporal information is gradually lost as information is passed through a layered network of mean-rate "units." We tested in humans w...

Congenitally deaf individuals receive little or no auditory input, and when raised by deaf parents, they acquire sign as their native and primary language. We asked two questions regarding how the deaf brain in humans adapts to sensory deprivation: (1) is meaning extracted and integrated from signs using the same classical left hemisphere frontotemporal network used for speech in hearing indivi...

Mechanisms of plasticity have traditionally been ascribed to higher-order sensory processing areas such as the cortex, whereas early sensory processing centers have been considered largely hard-wired. In agreement with this view, the auditory brainstem has been viewed as a nonplastic site, important for preserving temporal information and minimizing transmission delays. However, recent groundbr...

There is compelling evidence that sensory processing impairments contribute to the cognitive and psychosocial dysfunction affecting the majority of schizophrenia (SZ) patients. An informative probe for sensory processing dysfunction in neuropsychiatric disorders is event-related potentials (ERPs) time-locked to presentations of deviant stimuli interspersed in a train of standard tones, which el...

Although interhemispheric interaction via the callosum is most often conceived as a mechanism for transferring sensory information and coordinating processing between the hemispheres, it will be argued here that the callosum also plays an important role in attentional processing. Experiments will be presented that support this viewpoint, both when attention is conceptualized as a resource and w...

Different areas of cerebral cortex are specialized for processing information from different sensory modalities, such as visual cortex, auditory cortex, and somatosensory cortex, and other areas are specialized for motor functions; however, all of these cortical areas have a similar internal anatomical organization and are more similar to each other in cytoarchitecture than they are to any othe...