Executive attention deficits after traumatic brain injury reflect impaired recruitment of resources

Abstract

Deficits in attention are a common and devastating consequence of traumatic brain injury (TBI), leading to functional impairments, rehabilitation barriers, and long-term disability. While such deficits are well documented, little is known about their underlying pathophysiology hindering development of effective and targeted interventions. Here we evaluate the integrity of brain systems specific to attentional functions using quantitative assessments of electroencephalography recorded during performance of the Attention Network Test (ANT), a behavioral paradigm that separates alerting, orienting, and executive components of attention. We studied 13 patients, at least 6 months post-TBI with cognitive impairments, and 24 control subjects. Based on performance on the ANT, TBI subjects showed selective impairment in executive attention. In TBI subjects, principal component analysis combined with spectral analysis of the EEG after target appearance extracted a pattern of increased frontal midline theta power (2.5–7.5 Hz) and suppression of frontal beta power (12.5–22.5 Hz). Individual expression of this pattern correlated (r = − 0.67, p < 0.001) with executive attention impairment. The grading of this pattern of spatiotemporal dynamics with executive attention deficits reflects impaired recruitment of anterior forebrain resources following TBI; specifically, deafferentation and variable disfacilitation of medial frontal neuronal populations is proposed as the basis of our findings.

Functional brain network mechanism of executive control dysfunction in temporal lobe epilepsy

“…In this study, we found that the strengthened theta connectivity was closely related to the EC network while performing the ANT. This finding is consistent with the belief that the theta synchronization activities in prefrontal cortices emerged during goal_ directed behavior tests [51][52][53][54]. Thus, decreased FC in theta band may contribute to the EC deficits in TLE patients.…”

Recovery from disorders of consciousness: mechanisms, prognosis and emerging therapies

“…Physiological correlates, in the form of shifts from B-type to C-type or D-type dynamics, associated with the transition from VS/UWS to MCS and higher levels of recovery, have been seen in some medication-responsive patients 29 and in patients who show spontaneous recovery during the acute 56 , 57 or subacute-to-chronic 54 stage of DoC. Recovery from VS/UWS or MCS to a confusional state or higher levels of cognitive function is typically associated with restoration of D-type dynamics 58 , 59 . Importantly, several specific predictions of the mesocircuit model and the ABCD model have been verified in groups of patients with acute and subacute-to-chronic DoC resulting from traumatic and non-traumatic causes 25 , 29 , 54 , 56 , 57 , 60 .…”

“…In patients who recover to the confusional state, restoration of tonic firing in the thalamus and D-type dynamics can coexist with local electrophysiologic abnormalities, for example, increased delta to alpha power ratios 59 . Patients who recover full consciousness can experience persistent cognitive dysfunction, owing to impaired arousal regulation from the anterior forebrain mesocircuit 58 . Ongoing neuronal dysfunction in these patients is proposed to result from restriction of the dynamic range of neocortical pyramidal neurons in the frontoparietal network and their loop connections with the basal ganglia and thalamus; evidence for a key role of the central thalamus in this restriction is accumulating 38 , 39 .…”

The Effects of Martial Arts Training on Attentional Networks in Typical Adults

“…Despite its central role in human adaptation to life, it is one of the most vulnerable cognitive functions. This is evidenced by the level of research showing the number of variables that deficits in attention can be attributed to, such as genetics ( Durston et al, 2006 ), mental illness ( Clark et al, 2002 ), and traumatic brain injury ( Shah et al, 2017 ), among others. Age has perhaps the biggest influence on attentional control with a large amount of research discussing the decline in this function in older adults ( Milham et al, 2002 ; Kray et al, 2004 ; Jennings et al, 2007 ; Deary et al, 2009 ; Carriere et al, 2010 ; Dorbath et al, 2011 ).…”