Dichotic listening deficits and the prediction of substance use in young boys

The Effect of Attention-Deficit/Hyperactivity Disorder and Methylphenidate Treatment on the Adult Auditory Temporal Order Judgment Threshold

PURPOSE

The Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition notes that attention-deficit/hyperactivity disorder (ADHD) diagnosed in childhood will persist into adulthood among at least some individuals. There is a paucity of evidence, however, regarding whether other difficulties that often accompany childhood ADHD will also continue into adulthood, specifically auditory processing deficits. The aim of this study was to examine the effect of ADHD and the stimulant medication methylphenidate on auditory perception performance among adults.

METHOD

A total of 33 adults diagnosed with ADHD according to Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition criteria (ADHD group) and 48 adults without ADHD (non-ADHD group) performed an auditory temporal order judgment task. Participants with ADHD performed the task twice: with and without taking methylphenidate (Ritalin), in random order.

RESULTS

Temporal order judgment thresholds of the ADHD group were significantly higher than those of the non-ADHD group. Methylphenidate significantly decreased temporal order judgment thresholds within the ADHD group, making their performance similar to the non-ADHD participants.

CONCLUSIONS

Auditory processing difficulties of those diagnosed with ADHD seem to persist into adulthood. Similar to findings with children, methylphenidate treatment improves performance on tasks requiring this ability among adults. Therefore, given the association between auditory temporal processing and linguistic skills, the beneficial effect of methylphenidate on adults' academic achievement may be accomplished by positively affecting auditory temporal processing. Further studies in this line of research are needed.

Language Disabilities, Comorbid Developmental Disorders and Risk for Drug Abuse in Adolescence

This paper deals with research which makes links between developmental problems such as language-learning disorders, attentional disorders, and behaviour disturbance on the one hand, and risk for misuse of alcohol and other drugs (AOD) in adolescence on the other. Poor academic performance is frequently cited as a risk for adolescent AOD misuse, however few workers have critically examined the role of linguistically-based academic sub-skills (e.g., oral and written language competence; strong social skills) which normally contribute to academic success, and hence operate as protective factors with respect to risk for AOD misuse. Studies which specifically address language skills and their association with risk for AOD misuse are reviewed, as are investigations which deal with patterns of comorbidity which are typically evident in clinical populations. Particular emphasis is placed on comorbidities between language-learning difficulties on the one hand, and behavioural or attentional disorders, on the other. It is argued that more explicitly investigating and intervening at the level of core language/social skill competencies might serve to strengthen protective factors in vulnerable groups. It is also noted that comorbid problems need to be considered as important covariates in studies of language disordered children and adolescents, rather than being treated as exclusionary criteria.