Attentional dysfunction and recovery in concussion: effects on the P300m and contingent magnetic variation

Abstract

MEG-evoked responses to the ANT reveal neurophysiological evidence of attentional dysfunction within days of injury. A pattern of improvement was also observed over the course of three months for the P300m, while behavioural performance did not change significantly. Further development of this method may yield a useful adjunct to neurological examination for concussion diagnosis and monitoring.

Regional Topological Aberrances of White Matter- and Gray Matter-Based Functional Networks for Attention Processing May Foster Traumatic Brain Injury-Related Attention Deficits in Adults

“…By utilizing the functional near-infrared spectroscopy (fNIRS) technique, Hibino et al reported significantly increased medial frontal activation and decreased lateral frontal activation in a small sample of young adult patients with severe TBI, as compared to healthy controls, during the performance of an attention task [ 19 ]. During the magnetoencephalography (MEG) recording, Petley et al showed reduced global activation and delayed reaction times when performing a visual attention task in patients with mild TBI compared to controls [ 20 ].…”

Magnetoencephalography abnormalities in adult mild traumatic brain injury: A systematic review

“…Of the nine papers that included task-based analyses; three assessed working memory ( Shah-Basak et al, 2018 , Popescu et al, 2019 , Huang et al, 2019cc ), two set-shifting ( da Costa et al, 2015 , Pang et al, 2016 ), and one visual attention ( Petley et al, 2018 ), visual tracking ( Diwakar et al, 2015 ), picture naming ( Popescu et al, 2017 ), and auditory information processing ( Kaltiainen et al, 2019 ). These tasks were performed during the MEG recording, while the analyses above only used resting state data.…”

“…The same group showed that connectivity between the occipital lobes and the rest of the brain in the alpha frequency band was reduced in mTBI participants compared to controls ( Pang et al, 2016 ). Petley et al showed reduced global field strength and delayed reaction times in a small sample of mTBI participants compared to controls during a visual attention task ( Petley et al, 2018 ). Visual tracking of an intermittently obscured target showed lower performance in mTBI participants and was associated with widespread relative changes in beta frequency band power compared to controls ( Diwakar et al, 2015 ).…”

“…While the mean time between MEG assessment and injury ranged from six days to 11 years in the papers incorporated in this systematic review, five papers included repeat MEG imaging sessions ( Lewine et al, 1999 , Kaltiainen et al, 2018 , Kaltiainen et al, 2019 , Li et al, 2018 , Petley et al, 2018 ). Three papers showed the incidence of abnormal LFA dropped as the interval between MEG imaging and injury increased, suggesting this represents an acute to subacute marker of injury that may also be linked to recovery ( Lewine et al, 1999 , Kaltiainen et al, 2018 , Li et al, 2018 ).…”

“…Given this discrepancy between longitudinal and cross-sectional study designs, it is not possible to ascertain whether excess LFA resolution is associated with symptomatic recovery from mTBI. Two of the papers with serial MEG imaging found that differences in task-based alpha frequency band power and event related potentials differentiated mTBI participants and controls acutely and 3–6 months later, suggesting the MEG abnormalities persist ( Petley et al, 2018 , Kaltiainen et al, 2019 ). Both papers noted that only small subsets of their samples returned for serial MEG sessions, which may have biased their results.…”