Article

Unilateral extinction is a common consequence of unilateral brain injury in which
individuals fail to detect a contralesional target when presented together with a
competing ipsilesional target. Here we review the literature on the different
mechanisms and anatomy hypothesized to underlie unilateral extinction. We argue
that extinction, which reflects a specific deficit in the simultaneous processing
of multiple briefly presented targets, should be distinguished from the failure
to actively explore and serially detect targets amongst distractors in
contralesional space commonly known as spatial neglect. While contralesional
sensory defects can be correlated with extinction, these sensory impairments
alone are usually not sufficient to explain the deficit.
Prototypical extinction
is instead best seen as the result of a pathologically biased competition between
multiple target representations for pathologically limited attentional resources.
The temporo-parietal junction (TPJ) is a critical site in many of the lesions
that provoke extinction. Additionally, the intraparietal sulcus (IPS) may play a
role in modulation of competitive interactions between multiple target
representations.
CI - Copyright (c) 2012 Elsevier Ltd. All rights reserved.

Langue : ANGLAIS