"They've made the first comparative study using nonhuman primates of the cerebral processing of voices, and they've done it with a noninvasive technique by training dogs to lie in a scanner".
Processing of voices was assessed in relation to processing of faces and names, in order to assess the modality- and material-specificity of any voice processing deficit.
Whereas semantic processing of voices is relatively easily investigated by adapting standard neuropsychological techniques, a detailed understanding of voice perception and its disorders will require the design of customized stimuli that allow particular vocal attributes to be isolated and manipulated.
On measures of perceptual processing of voices, the Alzheimer's disease group (but not the temporal lobe variant FTLD group) showed deficits relative to healthy controls, suggesting that impairments of voice perception may show relative specificity for Alzheimer's disease.
In particular, this study showed using intracerebral depth electrodes that the evoked responses of the left, but not the right primary auditory cortex are differential for the processing of voiced and voiceless consonants and their non-speech analogues.
In this test we aimed to assess different aspects of semantic processing of famous voices (voice recognition) comprising familiarity, naming, identification from biographical information and cross-modal matching, in comparison to recognition of faces and names for the same famous individuals.
Although the initial processing of the vOICe's soundscapes occurred in the auditory cortex, subsequent tasks, such as identifying objects, occurred in the same regions of the brain as in sighted people.
Fig. 16 Sequence diagram describing processing of a voice command.
Interestingly, the processing of familiar voices or identifying the individual identity of voices likewise elicits right hemispheric dominant brain responses (Levy et al., 2001; Nakamura et al., 2001).
