Awareness of deficits and error processing after traumatic brain injury

Abstract

Severe traumatic brain injury is frequently associated with alterations in performance monitoring, including reduced awareness of physical and cognitive deficits. We examined the relationship between awareness of deficits and electrophysiological indices of performance monitoring, including the error-related negativity and posterror positivity (Pe) components of the scalp-recorded event-related potential, in 16 traumatic brain injury survivors who completed a Stroop color-naming task while event-related potential measurements were recorded. Awareness of deficits was measured as the discrepancy between patient and significant-other ratings on the Frontal Systems Behavior Scale. The amplitude of the Pe, but not error-related negativity, was reliably associated with decreased awareness of deficits. Results indicate that Pe amplitude may serve as an electrophysiological indicator of awareness of abilities and deficits.

Electrophysiological markers of cognitive deficits in traumatic brain injury: A review

“…An ERN source localised to anterior cingulate regions, was produced both when participants were and were not aware of their error, but the subsequent error positivity (Pe) component was enhanced only when participants were aware of committing an error. These findings, together with those reported by Larson et al (2007Larson et al ( , 2009, tentatively suggest that although preconscious action monitoring mechanism may be dysfunctional, TBI patients exhibit normal conscious evaluation after an error is committed as indexed by an intact Pe, at least in the context of high conflict colour-word stimuli. However, it remains to be seen as to whether patients would still show a robust Pe response under conditions that engender attentional drift such as tasks with low conflict demand (e.g.…”

“…This is the first ERP marker that suggests inefficiencies in performance monitoring in TBI patients. Recently it has also been reported (Larson and Perlstein, 2009) that the amplitude of the Pe, but not ERN, was reliably associated with decreased awareness of deficits as measured by discrepancy scores of self and family reports from the Frontal Systems Behavioural Scale.…”

Evaluation of traumatic brain injury: Brain potentials in diagnosis, function, and prognosis

“…Only one study (Larson and Perlstein, 2009) found an altered Pe in TBI patients: In this study, Pe amplitude was associated with "awareness of deficit," defined as the discrepancy between survivor and primary caregiver ratings on the Frontal Systems Behavioral Scale (Grace and Malloy, 2001). Less awareness of deficits was associated with smaller Pe amplitudes, suggesting that Pe reflects a control process that underlies awareness of deficits and performance errors.…”

“…Research from the Perlstein and Larson laboratories has demonstrated altered ERN, Pe, and FRN components of the ERP in survivors of severe TBI, suggesting impairment in performance monitoring, contingency sensitivity, and reward prediction (Larson et al, 2007a(Larson et al, , 2007b(Larson et al, , 2009a(Larson et al, , 2009bLarson and Perlstein, 2009). The finding of impaired sensitivity to reward context adds to the results of other studies indicating that, in comparison to healthy subjects, severe TBI leads to difficulties in monitoring one's own performance and in altering behavior in response to environmental cues, whether indicative of positive or negative consequences.…”

“…This suggests that brain injury, when sufficient in severity, diminishes and delays the available resources necessary to evaluate and monitor both internal and external events and states. Thus, when modifications in behavior are needed, the error signal is more difficult to implement (e.g., Larson et al, 2007aLarson et al, , 2009bLarson and Perlstein, 2009). From the perspective of cognitive control research, the key terms to describe the normal corrective processes are evaluate and regulate.…”