Table 2.

Studies investigating the effects of visual and sensorimotor performance on concussion risks

	Participants	Assessments	Relationships between visual and sensory performance and head impacts					Findings	Limitations
			Visual and sensory measure	Linear head acceleration	Rotational head acceleration	HIT severity profile	Head impact frequency
Harpham et al. [57]	38 Div I college American Football players (20.4 ± 1.4 years; 190.2 ± 6.7 cm; 109.3 ± 17.8 kg)	Nike SPARQ sensory station Head Impact Telemetry system General linear mixed models to test relationship between visual performance and impact severity	Visual clarity (SVA) Contrast sensitivity Depth perception Near-far quickness Target capture (DVA) Perception span Eye-hand coordination Go/No go decision making Reaction time	– ↓ Risk ↓ Risk ↓ Risk – – ↓ Risk ↓ Risk	– – – ↓ Risk ↓ Risk ↓ Risk ↓ Risk ↓ Risk ↓ Risk	N/A	N/A	High performers on certain assessments were at lower risk of concussion	Small convenience sample: various player positions, single team, 1 playing season Arbitrary cut-offs for ‘high’ and ‘low’ performers on Nike SPARQ station
Schmidt et al. [58]	37 male high school American Football players (16.59 ± 0.89 years; 180.35 ± 6.39 cm; 87.18 ± 19.03 kg)	Nike SPARQ sensory station Head Impact Telemetry Assessed odd ratios for sustaining moderate and severe head impacts	Visual clarity (SVA) Contrast sensitivity Depth perception Near-far quickness Target capture (DVA) Perception span Eye-hand coordination Go/No go decision making Reaction time	– – – – – – – – ↑ Odds2	– – – – – – – – ↑ Odds2	– – – ↑ Odds1 – – – – ↑ Odds1	N/A	Using a median split to classify high and low performers, higher performers did not reduce the odds of sustaining high-magnitude impacts	Small convenience sample: various player positions, single team, 1 playing season Arbitrary cut-offs for ‘high’ and ‘low’ performers on Nike SPARQ station
Kiefer et al. [53]	12 male high school ice hockey players (16.50 ± 1.17 years; 177.79 ± 6.83 cm; 70.32 ± 7.19 kg)	Oculomotor performance Head acceleration 3 tasks: - Prosaccade task - Self-paced saccade task - Smooth pursuit task	Prosaccade latency Prosaccade latency variability Self-paced saccade velocity Self-paced saccade initial error Medium-speed smooth pursuit latency Medium-speed smooth pursuit gaze velocity variability Fast-speed smooth pursuit gaze velocity variability	N/A	N/A	N/A	– ↓ Risk ↑ Risk – – ↓ Risk –	More variable oculomotor reaction time, faster saccadic eye motion and more variable gaze velocity when following a predictable target trajectory were related to an increased risk of head impacts Higher variability of saccade latency and smooth pursuit tracking may indicate a lack of attention to task-relevant visual cues necessary to avoid collisions There were no changes in concussion risk when accounting for accuracy of the self-paced saccade task	Small convenience sample: various player positions, single team, 1 playing season Combination of anticipated and unanticipated hits analysed; no analysis of whether the impact was anticipated or not

¹For moderate (HITsp: 11.7–15.7) and severe (HITsp: ≥ 15.7) head impacts

²For moderate (HITsp: 11.7–15.7) head impacts, but only tended to increase the odds

DVA dynamic visual acuity