A delay in the process of decision making and reaction time might result in potential errors in knee positioning and thereby pose an increased risk for ACL injury. This reaction time and processing speed can be classified as neurocognitive performance. Although neurocognitive performance seems crucial in recovery after ACL injury there is a lack of evidence if and how it contributes to ACL injuries.
Neurocognition and visual processing
It was found that several studies tested neurocognition and visual processing in athletes after ACL injury: one study showed reduced neurocognitive and visual processing abilities, whereas another study found the opposite. The tests applied in these studies were extremely different which might be an explanation of these contradictory findings.
Added cognitive load
Several studies investigated added cognitive load in ACL-injured athletes. The majority of the studies demonstrated that either ACL-injured athletes sacrificed their cognitive performance to maintain enough postural control or depending on the chicken and egg question that postural stability declined with additional cognitive load. Only one study did not identify any differences.
Central nervous system (CNS)
Furthermore, ten studies investigated the role of the CNS and suggested that ACL injured athletes show different functional connectivity in the CNS. They were also able to link it to altered neurophysiological features. Two studies demonstrated that these changes persisted even years after the injury.