The normal and aphasic groups both demonstrated significant activation for Sp comprehension in similar bilateral temporal regions that included left anterolateral STC (Fig. 1A; Supplementary Table 1).
As for the larger study, it was reported that the performance of children with bilateral CIs on spoken language comprehension and expression was superior.
In previous studies, we have also found bilateral frontal activity in syntactic comprehension in older participants, with right inferior frontal gyrus activity correlated with decreasing integrity in left inferior frontal gyrus in the context of preserved syntax.
The results for the Total Language and Auditory Comprehension subscales show that bilateral CIs predicted significant language improvements by 5 years of age, provided they were activated early enough.
A large comprehension network was found across bilateral Superior Temporal Sulcus (STS), Middle Temporal Gyrus (MTG and Superior Temporall (STS) bilaterally, in left Inferior Frontal Gyrus (IFG), left Precentral Gyrus, and Supplementary Motor Area SMAandand pre-SMA.
The dynamic changes observed in this longitudinal fMRI study support the increasing role of bilateral BAs 21 and 22 in narrative comprehension, involving non-domain-specific integration in order to achieve final story interpretation.
This is with reference to deficits pertaining to functions mediated by dorsolateral prefrontal cortex (poor performance on tests of attention, fluency and working memory), right parietal (poor performance on tests of visuospatial functions) and bilateral temporal cortex (poor performance on tests of comprehension, verbal learning, and memory for verbal and visual material).
Results indicated that, regardless of the aspect of sentence comprehension being controlled for, activation was observed in bilateral temporal lobes (left > right) as well as bilateral occipital lobes and middle frontal gyri.
Neuroimaging studies with healthy participants show the involvement of bilateral superior, middle, and inferior temporal areas in language comprehension [Hickok and Poeppel, 2007], often with little evidence of left frontal activation [e.g., Tyler et al., 2010].
There is growing consensus concerning the network of brain regions that support the comprehension of connected speech, which minimally include bilateral superior temporal cortex, more extensive left superior and middle temporal gyri, and left inferior frontal cortex (Bates et al. 2003; Davis and Johnsrude 2003, 2007; Scott and Johnsrude 2003; Peelle et al. 2010).
Two of the three PLS-4 bilateral age activation windows were nonempty (Total Language and Auditory Comprehension), implying that a bilateral child will already be demonstrating improved language outcomes by 5 years of age, provided they receive their second implant sufficiently early.
