Brain activation during neurocognitive testing using functional near-infrared spectroscopy in patients following concussion compared to healthy controls

Abstract

There is no accepted clinical imaging modality for concussion, and current imaging modalities including fMRI, DTI, and PET are expensive and inaccessible to most clinics/ patients. Functional near-infrared spectroscopy (fNIRS) is a non-invasive, portable, and low-cost imaging modality that can measure brain activity. The purpose of this study was to compare brain activity as measured by fNIRS in concussed and age-matched controls during the performance of cognitive tasks from a computerized neurocognitive test battery. Participants included nine currently symptomatic patients aged 18–45 years with a recent (15–45 days) sport-related concussion and five age-matched healthy controls. The participants completed a computerized neurocognitive test battery while wearing the fNIRS unit. Our results demonstrated reduced brain activation in the concussed subject group during word memory, (spatial) design memory, digit-symbol substitution (symbol match), and working memory (X’s and O’s) tasks. Behavioral performance (percent-correct and reaction time respectively) was lower for concussed participants on the word memory, design memory, and symbol match tasks than controls. The results of this preliminary study suggest that fNIRS could be a useful, portable assessment tool to assess reduced brain activation and augment current approaches to assessment and management of patients following concussion.

Assessing prefrontal cortex oxygenation after sport concussion with near‐infrared spectroscopy

“…Second, a cross‐sectional design does not allow for application of this project's recovery trends for oxyhaemoglobin concentration and its variances, to a single patient in a clinical setting. And third, the present study, in addition to the other NIRS‐concussion literature (Kontos et al ., ; Urban et al ., ), all have such unique methodologies and procedures, that it hinders the ability to draw a broader conclusion about the use of NIRS with concussion. Said differently, a hallmark of science is independent reproduction of an experiment, where one must be able to come to a similar outcome.…”

“…Briefly, the first haemoglobin‐concussion publication utilized functional NIRS (fNIRS) to measure relative haemoglobin changes in the frontal lobe and assessed the coupling of cortical activity to metabolite delivery during the ImPACT test. In general, the results showed that concussed participants, (who were still exhibiting symptoms 15–45 days post‐injury), had less changes in oxyhaemoglobin (HbO 2 ) during the ImPACT test and performed worse on the test outcomes when compared to controls (Kontos et al ., ).…”

“…The above statement indicates an inability of the ImPACT test to consistently align healthy asymptomatic patients with no cognitive impairments (and vice versa) and suggests that the ImPACT test results likely must be considered in terms of physiological impairments (Talavage et al, 2010;Fox, 2011;Iverson et al, 2012;Kontos et al, 2014;Bigler, 2015). Moreover, there are other concussion management practices which rely on balance testing pre-and post-injury (Guskiewicz, 2011).…”

“…To solve this concussion biomarker issue, some brain injury researchers have examined the frontal lobe's contribution to medullary function, which includes understanding how a loss of brain function exerts its effect on healthy variance of other physiological systems (Lang et al, 2003;Zweifel et al, 2008Zweifel et al, , 2010Ryan et al, 2011;Thayer et al, 2012;Len et al, 2013;Kontos et al, 2014;Blake et al, 2015;Urban et al, 2015;Bishop et al, 2017). This is because the frontal lobe can alter both the medulla's capacity to monitor the unconscious processes (such as cardiorespiratory status), and conscious processes such as reaction time and word recall (Goodale & Milner, 1992;Lovallo, 2005;Sakagami et al, 2006;Taylor et al, 2010).…”

Classification of Functional Near-Infrared Imaging Based Hemodynamic Patterns Recorded at Mental Arithmeti̇c and Resting

“…It is desired to determine changes in hemoglobin (Hb) concentration of brain tissues. According to this method, brain functions related to non-invasive oxygenation, changes in blood oxygenation and blood density are displayed by viewing the blood flow in the forebrain [3]. Metabolic responses arising as a result of each task, such as oxy-and deoxyhemoglobin changes during a point-offocus, allow the using of fNIRS or hybridization of electroencephalogram (EEG) and fNIRS in BCI systems.…”