Auditory extinction: the effect of stimulus similarity and task requirements

Aphasia and auditory extinction: Preliminary evidence of binding

“…One cognitive process that has been a focus of recent research is the role of "binding" information in auditory and visual perception (Baylis, Driver, & Rafal, 1993;Baylis, Gore, Rodriguez, & Shisler, 2001;Shisler, Gore, & Baylis, 2004). Binding refers to the integration of sensory information (identification and location) into a whole, thus resulting in the perception of an object or event.…”

“…The idea that attention is necessary for the binding together of different aspects of visual stimuli was proposed by Treisman and Gelade (1980), and the importance of attention in solving the binding problem has been emphasised by many researchers (e.g., Reynolds & Desimone, 1999). Recent research suggests that individuals with right hemisphere (RH) brain damage have difficulty in binding identification and localisation information in vision (Baylis et al, 2001) and audition (Shisler et al, 2004) due to deficits in attention.…”

“…Extinction is typically defined as a failure to respond to a contralesional target during simultaneous presentations of stimuli to both the left and right hemifields, known as double simultaneous stimulation or DSS (Marzi et al, 1996), and is not considered to be due to a sensory deficit (Baylis et al, 2001;Shisler et al, 2004). For example, during DSS, individuals with RH lesions with extinction have shown decreased contralesional performance when asked to respond to two simultaneous targets (left and right) (Baylis et al, 2001;Shisler et al, 2004); however, participants are typically able to correctly identify a single stimulus presented in the contralesional hemifield (single left presentation). Due to the fact that individuals are able to identify a single stimulus on the contralesional side, many researchers have argued that extinction is caused by a deficit in attention and not due to sensory difficulties per se (Baylis et al, 1993;Volpe, LeDoux, & Gazzaniga, 1979).…”

“…Baylis et al (1993) argued that in patients with unilateral RH lesions, specific features may not be combined in the contralateral field, resulting in extinction. Therefore, when deficits in attention are present, as in individuals with RH damage, patients may not be aware of contralesional stimuli because identification and location information was not bound together properly (Baylis et al, 1993(Baylis et al, , 2001Shisler et al, 2004). Further support related to extinction came from .…”

“…Additionally, Shisler et al (2004) found that when patients with RH damage were presented with auditory stimuli in a double simultaneous stimulation (DSS) task that required binding of identification and localisation, participants demonstrated significant extinction for information presented to the left; however, in a similar task that did not require binding, omissions decreased for DSS items presented contralesionally. Note that during this task when single items were presented to the left or right, patients made very few errors.…”