Thinner Cortex in Collegiate Football Players With, but not Without, a Self-Reported History of Concussion

Abstract

Emerging evidence suggests that a history of sports-related concussions can lead to long-term neuroanatomical changes. The extent to which similar changes are present in young athletes is undetermined at this time. Here, we tested the hypothesis that collegiate football athletes with (n = 25) and without (n = 24) a self-reported history of concussion would have cortical thickness differences and altered white matter integrity relative to healthy controls (n = 27) in frontotemporal regions that appear particularly susceptible to traumatic brain injury. Freesurfer software was used to estimate cortical thickness, fractional anisotropy was calculated in a priori white matter tracts, and behavior was assessed using a concussion behavioral battery. Groups did not differ in self-reported symptoms ( p > 0.10) or cognitive performance ( p > 0.10). Healthy controls reported significantly higher happiness levels than both football groups (all p < 0.01). Contrary to our hypothesis, no differences in fractional anisotropy were observed between our groups ( p > 0.10). However, football athletes with a history of concussion had significantly thinner cortex in the left anterior cingulate cortex, orbital frontal cortex, and medial superior frontal cortex relative to healthy controls ( p = 0.02, d = -0.69). Further, football athletes with a history of concussion had significantly thinner cortex in the right central sulcus and precentral gyrus relative to football athletes without a history of concussion ( p = 0.03, d = -0.71). No differences were observed between football athletes without a history of concussion and healthy controls. These results suggest that previous concussions, but not necessarily football exposure, may be associated with cortical thickness differences in collegiate football athletes.

Smaller Dentate Gyrus and CA2 and CA3 Volumes Are Associated with Kynurenine Metabolites in Collegiate Football Athletes

“…20 There was no significant relationship between KYN metabolites and cortical thickness in either football athlete groups ( p's > 0.05). The ratio of KYNA/3HK, however, was correlated with cortical thickness in the left ventromedial PFC in HC (q 21 = 0.48, r = 0.39, p = 0.026; Fig.…”

“…20 A positive correlation between left ventromedial PFC thickness and KYNA/3HK was observed, however, in HC, and left hippocampal volume was significantly correlated with cortical thickness in both regions in HC but not in either football athlete group. The positive relationship between KYNA/3HK and left ventromedial PFC in HC is consistent with the hypothesis that KYNA/3HK is a neuroprotective measure given the respective actions of KYNA and 3HK in the CNS.…”

“…Behavioral data for this cohort are presented in a separate article investigating differences in cortical thickness and fractional anisotropy and are not reported here. 20 Magnetic resonance imaging (MRI)-parameters and subfield segmentation MRI was performed using a GE Discovery MR750 3-Tesla whole body MRI scanner (General Electric Healthcare) and braindedicated receive-only 32-element coil array optimized for parallel imaging (Nova Medical, Inc.). T1-weighted anatomical images were collected using a parallelized magnetization-prepared rapid gradient-echo sequence (MPRAGE) with sensitivity encoding and the following parameters for all participants: FOV = 240 mm, 130 axial slices, slice thickness = 1.1 mm, image matrix = 256 · 256, voxel size 0.9375 · 0.9375 · 1.1 mm, TR/TE = 5/1.948 msec, acceleration factor R = 2 in the phase encoding direction, flip angle = 8 degrees, TI = 725 msec, sampling bandwidth = 31.25 kHz, scan time = 5:05 min.…”

Sports Concussion: A Clinical Overview

“…In 2012, a systematic review of the DTI and concussion literature [65] reported on eight studies and raised concern in the literature at the time that there was so much variability in the methodology bringing together the findings of the diverse range of work and attempting to interpret the results was challenging. A more recent DTI and concussion systematic review [49] suggested that the most consistent findings were decreased mean diffusivity and/or an increase in fractional anisotropy in white matter within 6 months post-concussion [66][67][68][69][70], but these findings are not universal (i.e., the opposite patterns have also been reported in other studies) [56,62,71]. In addition, reduced radial diffusivity has been reported [68,[72][73][74], but increase and decrease in axial diffusivity have been described [68,69].…”

A Historical Perspective on Sports Concussion: Where We Have Been and Where We Are Going

“…Recent studies have used traditional imaging techniques to identify thinning of the cerebral cortex in collegiate American football athletes with a documented history of concussion compared to football players without a noted history of concussion as well as non-athletes [21]. A recent retrospective study looked into the prevalence of cavum septum pellucidum (CSP) in retired professional American football athletes who presented to a memory clinic and identified a significantly higher prevalence of CSP in football players compared to controls [22].…”