The auditory cortex can be divided into primary auditory cortex (PAC), secondary auditory cortex (SAC), and auditory association
Four subtests from the Illinois Test of Psycholinguistic Abilities (ITPA; Kirk, McCarthy, & Kirk, 2001) were administered: (a) Auditory Comprehension, the child listens to stories and responds to questions about them by pointing to pictures; (b) Auditory Association, the child completes sentences spoken by the examiner; (c) Verbal Expression, a lexical fluency task in which the child says as many items in a stated category as possible in one minute; and (d) Grammatical Integration, the child completes sentences spoken by the examiner according to pictures; (see Girbau & Schwartz, 2007a, 2008, for additional information).
Only a weak correlation was observed for children with TLD between priming and the Auditory Association subtest score, r = -.58, p = .03.
In 1968 Geschwind and his then student Walter Levitsky had shown in the general population that the planum temporale, comprising part of the auditory association
cortex involved in linguistic functions, was large on the left and small on the right, perhaps explaining language lateralization to the left hemisphere.
In oral language, auditory input is transmitted from the medial geniculate nucleus in the thalamus to both primary auditory areas (PA) and auditory association areas (AA), the latter of which may contain phonologic representations of words (Binder et al., 1994).
Adults showed significantly more activation in fusiform gyrus (FG) during reading tasks and more activation in auditory association areas (AA) during oral language tasks (see Figures 2 and 3).
An alternative explanation is that boys create visual and auditory associations
such that meanings associated with a word are brought to mind simply by seeing or hearing the word.
Since in normal circumstances, the auditory associations
of speech completely overshadow the visual, in experimental demonstrations the auditory signal has been degraded to emphasize the visual contribution.