Sustained attention in traumatic brain injury (tbi) and healthy controls: enhanced sensitivity with dual-task load

Abstract

Poor sustained attention or alertness is a common consequence of traumatic brain injury (TBI) and has a considerable impact on the recovery and adjustment of TBI patients. Here, we describe the development of a sensitive laboratory task in healthy subjects (Experiment 1) and its enhanced sensitivity to sustained attention errors in TBI patients (Experiment 2). The task involves withholding a key press to an infrequent no-go target embedded within a predictable sequence of numbers (primary goal) and detecting grey-coloured targets within the sequence (secondary goal). In Experiment 1, we report that neurologically healthy subjects are more likely to experience a lapse of attention and neglect the primary task goal, despite ceiling performance on the secondary task. Further, attentional lapses on the task correlated with everyday attentional failures and variability of response time. In Experiment 2, the task discriminates between TBI patients and controls with a large effect size. The dual-task yields more errors in both groups than a simple task involving only the primary goal that is commonly used to detect sustained attention deficits in neurologically impaired groups. TBI patients' errors also correlated with everyday cognitive failures and variability of response time. This was not the case in the simple version of the task. We conclude that the dual-task demand associated with this task enhances its sensitivity as a measure of sustained attention in TBI patients and neurologically healthy controls that relates to everyday slips of attention.

Awareness of deficits in traumatic brain injury: A multidimensional approach to assessing metacognitive knowledge and online-awareness

“…Furthermore, in a related study, a switch cost was observed on the dual-task version of the SART in which the dual-task element, rather than making a verbal response, was to respond with a different key press to a grey digit. In that study, the dual-task switch cost was equal for TBI participants and controls (Dockree et al, 2006). We therefore feel that although switch costs will exist in tasks with dual-task elements, these switch costs do not interfere with the primary aim of assessing emergent awareness.…”

“…These included: National Adult Reading Test (NART) (Nelson, 1982;Nelson & Willison, 1991), Hospital Anxiety and Depression Scale (HADS) (Zigmond & Snaith, 1983), Frenchay Aphasia Screening Test (FAST) (Enderby et al, 1987), and Frontal Assessment Battery (FAB) (Dubois et al, 2000). (Robertson et al, 1996) and the Sustained Attention to Response Task (Robertson et al, 1997, Manly et al, 2003, Dockree et al, 2006. Participants undertook three tasks of sustained attention: the Fixed SART, Random SART and the DART.…”

Neuropsychology and clinical neuroscience of persistent post-concussive syndrome

“…In other words, unless a significant cognitive demand was placed on the subject that required more than typical cognitive effort, no differences could be determined. Similarly, Bernstein (2002) demonstrated that by increasing the complexity of a dual task involving auditory and visual discrimination and measuring evoked responses that those with a history of concussion but ostensibly no residual complaints could be differentiated from controls (Dockree et al, 2006a).…”

Neurocognitive and Biomarker Evaluation of Combination mTBI from Blast Overpressure and Traumatic Stress

“…While 20 further studies are needed to confirm this possibility, it is notable that failures of inhibitory control behaviors are integral features of many psychiatric disorders and the mechanism of an inhibitory control system in rats has been the subject of substantial study (see review by Eagle and Baunez, 2010). Furthermore, deficits in behavioral inhibition have been observed in patients following TBI (Dimoska-Di Marco, et al, 2011;Dockree, et al, 2006;O'Keeffe, et al, 2007).…”