objectives: one of the issues that have consistently been the concern for the health affair specialists and cure and massive social governors in health fields is the rate of disorders prevalence, diseases and the related subjects to epidemiology. purpose of this study was to estimate the prevalence of mathematic disability amongst primary schools of karaj. methods: totally 432 students were sel...

The integration of visual and auditory events is thought to require a joint representation of visual and auditory space in a common reference frame. We investigated the coding of visual and auditory space in the lateral and medial intraparietal areas (LIP, MIP) as a candidate for such a representation. We recorded the activity of 275 neurons in LIP and MIP of two monkeys while they performed sa...

Physical models of biomolecular components and their interactions are extraordinarily useful aids in understanding complex biological structure and organization. With our collaborators at The Scripps Research Institute (TSRI) and the University of Utah we are exploring the production of such models through autofabrication technology, and augmenting them with a variety of interface modalities, i...

Brain-computer interfaces (BCIs) can serve as muscle independent communication aids. Persons, who are unable to control their eye muscles (e.g., in the completely locked-in state) or have severe visual impairments for other reasons, need BCI systems that do not rely on the visual modality. For this reason, BCIs that employ auditory stimuli were suggested. In this study, a multiclass BCI spellin...

Many educators have argued for and against the use of remote aids in support of student learning. Some proponents argue that only remote laboratories should be used whereas others argue for the requirement for hands on experience with associated tactical, visual and auditory learning experiences. In this paper we present the methodology for developing a middle ground Virtual Instruments that ca...

The present study investigated whether dividing critical information across the hemispheres in the auditory and tactile modalities aids performance more for computationally complex rather than computationally simpler task-a pattern previously observed in the visual modality [Cortex 26 (1990) 77; Neuropsychology 12 (1998) 380; Neuropsychologia 30 (1992) 923]. We conducted two experiments, one in...

Localizing a sound source requires the auditory system to determine its direction and its distance. In general, hearing-impaired listeners do less well in experiments measuring localization performance than normal-hearing listeners, and hearing aids often exacerbate matters. This article summarizes the major experimental effects in direction (and its underlying cues of interaural time differenc...

The neural mechanisms underlying attentional selection of competing neural signals for awareness remains an unresolved issue. We studied attentional selection, using perceptually ambiguous stimuli in a novel multisensory paradigm that combined competing auditory and competing visual stimuli. We demonstrate that the ability to select, and attentively hold, one of the competing alternatives in ei...

PURPOSE To determine the effect of hearing loss (HL) on children's performance for an auditory task under demanding listening conditions and to determine the effect of digital noise reduction (DNR) on that performance. METHOD Fifty children with normal hearing (NH) and 30 children with HL (8-12 years of age) categorized words in the presence of auditory or visual competitors, or both. Stimuli...

To investigate the cross-modal nature of the exogenous attention system, we studied how involuntary attention in the visual modality affects ERPs elicited by sudden onset of events in the auditory modality. Relatively loud auditory white noise bursts were presented to subjects with random and long inter-trial intervals. The noise bursts were either presented alone, or paired with a visual stimu...