Neuronuclear imaging research associate

Objectives: We previously described regional- and position- specific changes in brain perfusion patterns in professional football players. (Raji et al, J Nucl Med. 2014; 55: 1880, No. 1990) In the present study, we examine the correlations between clinical symptoms and changes in blood flow in offensive linemen (OL) and defensive backs (DB).

Methods: A total of 45 men who were on an active NFL roster for at least 3 years and played as OL (n=25, mean age 56 ± 3) or DB (n=20, mean age 60 ± 2) underwent 99mTc-HMPAO SPECT with a Picker 3-headed camera as they performed an attention-focusing cognitive task. Participants also underwent the MicroCog Assessment of Cognitive Functioning for evaluation of cognitive status in five domains that include attention, memory, reasoning, spatial ability, and reaction time. Regional pattern of blood flow in the brain of each participant was assessed by standardized volumes of interest (sVOI) and statistical parametric mapping (spm) methods. Correlations between brain regions and scores on various neuropsychological variables was evaluated using the Pearson correlation coefficient. A two-tailed t-test was performed and a p-value based on the t-value for r² was generated, with p-values ≤ 0.001 corresponding to survival of a Bonferroni-type correction.

Results: sVOI analyses displayed a highly significant correlation between spatial ability and left associative visual cortex in OL (r=0.64, p=0.0006), but not among DB (r=0.31, p>0.05). Conversely, there was a significant correlation between spatial ability and right posterior cingulate cortex in DB (r=0.72, p=0.0003), but not in OL (r=0.04, p>0.05). SPM analyses revealed a significant correlation between spatial ability and right superior parietal cortex in OL (peak voxel [14, -62, 60], t=3.92, p=0.0005; cluster size=109,450 voxels, p=0.001, p=0.003 FWE corr.). SPM also showed a significant correlation between reaction time and left medial frontal cortex in all players (peak voxel [-32, 44, 28], t=4.69, p=0.0005, p=0.04 FWE corr.; cluster size=3253 voxels, p=0.029).

Conclusion: History of NFL play is associated with position-specific correlations between regional cerebral blood flow and neuropsychologic measures. Research Support: N/a