Biomedical subjects

Matthew S Tata

Publications and source records attributed to Matthew S Tata.

4 recordsLinked to original sources

PubMed2005

Early phase of spatial mismatch negativity is localized to a posterior "where" auditory pathway.

The auditory mismatch negativity (MMN) is an event-related potential that reflects early processing of changes in acoustic stimulus features. Although the MMN has been well characterized by previous work, the number, roles, and anatomical locations of its cortical generators remain unresolved. Here, we report that the MMN elicited by occasional deviations in sound location is comprised of two temporally and anatomically distinct phases: an early phase with a generator posterior to auditory cortex and contralateral to the deviant stimulus, and a later phase with generators that are more frontal and bilaterally symmetric. The posterior location of the early-phase generator suggests the engagement of neurons within a putative "where" pathway for processing spatial auditory information.

Acoustic Stimulation↗

PubMed2004

Spatial attention modulates activity in a posterior "where" auditory pathway.

Selectively listening to a single location in space modulates both the behavioral and electrophysiological responses to auditory stimuli presented at that location. Transient attention oriented in cue-target or target-target paradigms results in several modulations of the auditory event-related potential known as the Nd1, Nd2, and Nd3. By employing electrical source analysis we tested the hypothesis that the earliest component (the Nd1) reflects modulation of neurons in parietal rather than auditory cortex. It was found that the most likely sources of the Nd1 modulation were posterior to primary auditory cortex within or near the temporo-parietal junction (TPJ). This location is within the putative auditory "where" pathway.

Adult↗

PubMed2003

Event-related potential evidence for attentional inhibition of return in audition.

Orienting attention to a spatial location facilitates responding to a subsequent target at that location, but inhibits the response if attention is oriented away from that location before the target appears there. This inhibitory effect of attention re-orienting, called inhibition of return (IOR), occurs in vision, hearing, touch, and cross-modally, and has been well studied behaviorally. However, little is known about its underlying neural mechanism(s). We report a study of the neural mechanism of auditory IOR using event-related potentials (ERPs). Auditory IOR was associated with elimination, but not reversal, of the Nd1 difference wave. Previous research indicates that the Nd1 represents an enhanced neural response to attended sounds. Also, auditory IOR was associated with a delay in the latency of the peak of the N1 component of the ERP at parietal sites. These effects are consistent with the accounts if inhibition of attention return that have been proposed for IOR, but are somewhat different from effects found in analogous ERP studies of visual IOR.

Adult↗

PubMed2002

Attend to it now or lose it forever: selective attention, metacontrast masking, and object substitution.

Metacontrast masking occurs when the visibility of a brief target stimulus is decreased by the subsequent appearance of another nearby visual stimulus. Early explanations of the phenomenon involved low-level mechanisms, but subsequent studies have suggested a role for selective attention. The results of three experiments presented here extend previous findings to the metacontrast paradigm. It is shown that the strength of metacontrast masking increases with the number of distractor items in a display, decreases when the target location is validly but not invalidly precued, and is eliminated when search for the target is efficient (pop-out search) but not when search is inefficient (serial search). A connection between metacontrast masking and object substitution masking is considered.

Attention↗