Neuropsychological Assessment of Distractibility in Mild Traumatic Brain Injury and Depression

Abstract

Traditional neuropsychological assessments are conducted exclusively in a quiet, distraction-free environment; clients’ abilities to operate under busy and distracting conditions remain untested. Environmental distractions, however, are typical for a multitude of real-life situations and present a challenge to clients with frontal-temporal brain injury. In an effort to improve ecological validity, an extension of the traditional neuropsychological assessment was developed, comprising a standardized distraction condition. This allowed cognitive functions to be tested both in the traditional setting and with exposure to a specified audio-visual distraction. The present study (n = 240) investigated how clients with mild Traumatic Brain Injury (mTBI) (n = 80), Major Depression (MDE) (n = 80), and a healthy control sample (n = 80) performed on sub-tests of the Wechsler Adult Intelligence Scale-IV and the Wechsler Memory Scale-IV both in the standard and the distraction conditions. Test effort was controlled. Significant deterioration of performance in the distraction setting was observed among clients with mTBI. In contrast the performance of a healthy control sample remained unchanged. Significant improvement of performance in the distraction setting was documented for clients with MDE. Contrary to their improved performance, depressed clients experienced the distraction setting as more distressing than the control and mTBI group.

Keywords:

• Environmental distraction
• Neuropsychological assessment
• Ecological validity
• Traumatic brain injury
• Major depressive episode

Notes

¹In nine cases GCS scores below 13 were documented upon admission which improved in A&E upon medical stabilization within 30 minutes.

²It is important to note the overlap between PCS symptoms and the BDI-II questions, including ambiguous items such as “concentration difficulties”, “problems with decision-making”, “low energy”, “fatigue”, “irritability” etc. MTBI clients inevitably score in the “mild symptom range” on the BDI-II when they endorse common PCS symptoms.