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Biology subjects

Champagne, A. A.

Publications and source records attributed to Champagne, A. A..

2 recordsLinked to original sources

Repeated subconcussive head impacts compromise white matter integrity: A longitudinal DTI and NODDI study in collegiate football players

ObjectivesTo determine whether repetitive subconcussive impacts in collegiate football are associated with altered white matter microstructure, motor control deficits, and changes in concussion symptoms across a single season. DesignCohort study with non-contact controls and stratification of contact athletes by head-impact exposure. MethodTwenty-two male varsity football players and 27 non-contact controls underwent pre-season diffusion tensor imaging. Tract-specific fractional anisotropy (FA) and mean diffusivity (MD) were derived from commissural and association tracts using probabilistic tractography. Helmet-mounted accelerometers quantified head-impact frequency and gForce over the season, classifying athletes into high (HE) and low-exposure (LE) groups. Football players completed the Kinarm Ball-on-Bar bimanual coordination task and SCAT3 symptom checklist pre- and post-season. ResultsAt pre-season, contact athletes showed altered white matter microstructure versus controls, with higher FA and predominantly lower MD across most tracts. Over the season, HE athletes sustained more total impacts and gForce than LE athletes and showed declining bimanual coordination on the Ball-on-Bar motor task. SCAT3 symptom and severity scores were low and showed no differences in change. ConclusionsRepetitive subconcussive exposure in collegiate football is associated with persisting white matter differences and subtle bimanual motor coordination deficits that are not detected by routine symptom-based tools, supporting the use of advanced neuroimaging and robotic motor assessment to monitor athlete brain health.

neuroscience↗

Spontaneous behavioural recovery following stroke relates to the integrity of sensory and association cortices

Stroke is a devastating disease that results in neurological deficits and represents a leading cause of death and disability worldwide. Following a stroke, there is a degree of spontaneous recovery of function, the neural basis of which is of great interest among clinicians in their efforts to reduce disability following stroke and enhance rehabilitation. Conventionally, work on spontaneous recovery has tended to focus on the neural reorganization of motor cortical regions, with comparably little attention being paid to changes in non-motor regions and how these relate to recovery. Here we show, using structural neuroimaging in a macaque stroke model and by exploiting individual differences in spontaneous behavioural recovery, that the preservation of regions in the sensory and association cortices predict animal recovery. To characterize recovery, we performed a clustering analysis using Non-Human Primate Stroke Scale (NHPSS) scores and identified a good versus poor recovery group. By comparing the preservation of brain volumes in the two groups, we found that brain areas in integrity of brain areas in parietal, temporal and somatosensory cortex were associated with better recovery. In addition, a decoding approach performed across all subjects revealed that the preservation of specific brain regions in the parietal, somatosensory and medial frontal cortex predicted recovery. Together, these findings highlight the importance of the sensory and association regions in spontaneous behavioural recovery, supporting the notion that the sensory retraining of impairments following stroke is critical to recovery and motor function.

neuroscience↗