Communication Sciences and Disorders Publications

The Contribution of Processing Impairments to SLI: Insights from Attention-deficit/Hyperactivity Disorder

Janis E. Oram Cardy et al. — Sat, 03 Mar 2012 19:21:32 PST

Slowed speed of processing and impaired rapid temporal processing (RTP) have been proposed to underlie specific language impairment (SLI), but it is not clear that these dysfunctions are unique to SLI. We considered the contribution of attention-deficit/hyperactivity disorder (ADHD), which frequently co-occurs with language impairments, to performances on processing tasks. School-aged children who had SLI without concurrent ADHD (n=14), ADHD without concurrent SLI (n=14), and typical development (TD, n=28) performed two nonverbal speeded tasks and one auditory RTP task. RTP impairments were found in many children with SLI and ADHD, and some children with TD. Children with ADHD demonstrated slower processing speed than children with SLI or TD. Overall, findings questioned the uniqueness of these processing dysfunctions to language impairments and the validity of the behavioural paradigms traditionally used to estimate processing dysfunctions. Accounts of SLI should be further scrutinized by considering the influence of other disorders. LEARNING OUTCOMES: Readers will (1) become familiar with areas of overlap between SLI and ADHD, (2) understand some of the confounds associated with behavioural measures of processing speed in children, and (3) recognize the value in testing models of language disorders by including participants with other types of disorders.

Stuttered Swallowing: Electric Stimulation of the Right Insula Interferes with Water Swallowing. A Case Report

Peter Sörös et al. — Fri, 08 Apr 2011 21:19:32 PDT

BACKGROUND: Various functional resonance imaging, magnetoencephalographic and lesion studies suggest the involvement of the insular cortex in the control of swallowing. However, the exact location of insular activation during swallowing and its functional significance remain unclear.

CASE PRESENTATION: Invasive electroencephalographic monitoring was performed in a 24-year-old man with medically intractable stereotyped nocturnal hypermotor seizures due to a ganglioglioma. During stimulation of the right inferior posterior insular cortex with depth electrodes the patient spontaneously reported a perception of a "stutter in swallowing". Stimulation of the inferior posterior insular cortex at highest intensity (4 mA) was also associated with irregular and delayed swallows. Swallowing was not impaired during stimulation of the superior posterior insular cortex, regardless of stimulation intensity.

CONCLUSIONS: These results indicate that the right inferior posterior insular cortex is involved in the neural circuitry underlying the control of swallowing.

Short-term and Working Memory in Children with Specific Language Impairment

Lisa M. D. Archibald — Thu, 24 Feb 2011 16:53:16 PST

Investigations of the cognitive processes underlying Specific Language Impairment (SLI) have implicated deficits in the storage and processing of phonological or verbal information. This thesis reports five studies that investigated the role of short-term and working memory in children with SLI. Study 1 demonstrated SLI deficits on measures of verbal working memory, and short-term memory for verbal but not visuospatial information. Study 2 provided evidence that children with SLI perform at age-level on visuospatial working memory measures. Study 3 demonstrated slower processing in the SLI group across domains, as well as verbal storage decrements, with the greatest deficits found for tasks tapping both of these. Study 4 found SLI deficits on measures of nonword repetition in common use, with greater impairments on the task that relied to a lesser extent on short-term memory. Study 5 established more accurate recall for multisyllabic nonwords than matched single syllable lists for all groups, although the SLI group showed different patterns of phoneme retention. It is suggested that the combination of deficits in generalized processing speed and verbal storage in SLI may be expected to have a drastic and detrimental impact on learning, and provides an account of the disorder that could encompass the range of impairments observed in SLI. The findings also suggest that factors additional to short-term memory contribute to poor nonword repetition in SLI.