Biomedical subjects

Brook Swainson

Publications and source records attributed to Brook Swainson.

3 recordsLinked to original sources

PubMed2007

Atypical lexical/semantic processing in high-functioning autism spectrum disorders without early language delay.

Although autism is associated with impaired language functions, the nature of semantic processing in high-functioning pervasive developmental disorders (HFPDD) without a history of early language delay has been debated. In this study, we aimed to examine whether the automatic lexical/semantic aspect of language is impaired or intact in these population. Eleven individuals with Asperger's Disorder (AS) or HFPDD-Not Otherwise Specified (NOS) and age-, IQ-, and gender-matched typically developing individuals performed a semantic decision task in four conditions using an indirect priming paradigm. Semantic priming effects were found for near-semantically related word pairs in the controls, whereas this was not the case in the AS or HFPDDNOS participants. This finding suggests similarities in the underlying semantic processing of language across PDD subtypes.

Adolescent↗

PubMed2006

Differentiation of speech and nonspeech processing within primary auditory cortex.

Primary auditory cortex (PAC), located in Heschl's gyrus (HG), is the earliest cortical level at which sounds are processed. Standard theories of speech perception assume that signal components are given a representation in PAC which are then matched to speech templates in auditory association cortex. An alternative holds that speech activates a specialized system in cortex that does not use the primitives of PAC. Functional magnetic resonance imaging revealed different brain activation patterns in listening to speech and nonspeech sounds across different levels of complexity. Sensitivity to speech was observed in association cortex, as expected. Further, activation in HG increased with increasing levels of complexity with added fundamentals for both nonspeech and speech stimuli, but only for nonspeech when separate sources (release bursts/fricative noises or their nonspeech analogs) were added. These results are consistent with the existence of a specialized speech system which bypasses more typical processes at the earliest cortical level.

Acoustic Stimulation↗

PubMed2004

Relationships of naming skills to reading, memory, and receptive vocabulary: evidence for imprecise phonological representations of words by poor readers.

The main hypotheses addressed in the research were (1) whether imprecision in the phonological representations of lexical items underlies the impaired expressive naming abilities of disabled readers, and (2) whether weak verbal memory might mediate the relationship between naming and reading skills. From samples of 93 first graders and 67 fourth graders, extreme groups of good and poor readers were identified and compared on measures of receptive vocabulary, expressive naming, acceptability judgments for variants of object names, imitation and correction of naming errors by another speaker, pseudoword repetition, and long-term memory. Performance was generally better by older than younger students and by good than poor readers at each age, with little interaction between grade and reader group. The results indicated that for both good and poor readers, imprecise phonological knowledge, especially about long words, contributed to children's difficulties on all naming tasks. Memory differences, however, appeared to play only a minor role in explaining the strong association between naming and reading.

Articulation Disorders↗