Effects of mild traumatic brain injury cannot be differentiated from substance abuse

PRIMARY OBJECTIVE

Patients involved in litigation relating to mild traumatic brain injury (MTBI) typically undergo a forensic neuropsychological evaluation. However, if cognitive problems are identified, it is difficult to know whether these are related to the MTBI or other factors such as pre- and/or post-injury substance abuse. The purpose of this study was to compare the neuropsychological test performances of 73 patients with acute, uncomplicated MTBIs to a sample of 73 patients from an inpatient substance abuse programme.

METHODS AND PROCEDURES

Patients were perfectly matched on age, education and gender. Ten cognitive measures were used that included the Trail Making Test (TMT) and selected sub-tests from the Wechsler Memory Scale-Revised.

MAIN OUTCOMES AND RESULTS

Patients with MTBI demonstrated poorer performances on Digits Backwards (p < 0.028) and TMTA (p < 0.032). There were no significant differences between the two groups on the remaining cognitive measures. The clinical usefulness of these measures to differentiate between the groups, using discriminant function analysis, was very poor.

CONCLUSIONS

Patients with uncomplicated MTBIs could not be reliably differentiated from patients with substance abuse problems on these measures of concentration, memory and processing speed.

Comparability of Neuropsychological Test Profiles in Patients with Chronic Substance Abuse and Mild Traumatic Brain Injury

The purpose of this study was to compare 104 patients with acute uncomplicated mild traumatic brain injury (MTBI) to a sample of 104 patients from an inpatient substance abuse program to determine whether these patients could be differentiated by their pattern of relative cognitive strengths and weaknesses. Patients were matched on age, education, and gender. Eight cognitive measures were used that included tests of attention, memory, and processing speed. There were no statistically significant differences between the two groups on any of the cognitive measures. Using a two-step cluster analysis procedure (i.e., hierarchical and k-means analyses), seven common profiles were identified. There was no significant difference in the proportions of patients from the MTBI or substance abuse group in each of the seven profiles. These results show that patients with uncomplicated MTBIs could not be reliably differentiated from patients with substance abuse problems on these cognitive measures. This is of particular concern for clinicians evaluating the neuropsychological effects of MTBI in individuals with a comorbid history of substance abuse.

A model of the effects of node-link mapping on drug abuse counseling

This paper examines the effectiveness of a promising cognitive enhancement technique called node-link mapping. Maps provide a concrete, visual, and computationally efficient means for exploring personal issues, and have received substantial empirical support. We introduce two models to provide a framework for understanding how node-link mapping improves substance abuse counseling. The TCU Process Model reviews the general process of substance abuse treatment. The second model reflects an effective treatment session. Implications of the models and node-link mapping findings are discussed, as well as future research directions.