Ichiro Suzuki, one of the most consistent batters in Major League Baseball, has been quoted saying that he refrains from watching poor batters in his team before going out to bat, because that affects his own batting performance. Other sports professionals have made similar observations but this has been largely considered a mere superstition. However, recent results from a study conducted by Tsuyoshi Ikegami (CiNet) and Gowrishankar Ganesh (CNRS-France) indicate that they were not so off the mark.

In their study, 22 highly-skilled darts players were asked to throw darts in between intermittent video sessions, where they watched novice dart throwers and learnt to predict the accuracy of the novice throws. Results showed that watching novice dart players leads to a progressive deterioration in the experts’ dart performance. Interestingly, performance deterioration was only induced when the experts could correctly predict the outcome of the novice throws.

These results show – for the first time – a causal effect between predicting the outcomes of observed actions on one’s motor performance, supporting the notion that prediction of other’s actions and action production are enabled by common neural circuits in the human brain. This has important ramifications for our understanding of social abilities in humans. It also suggests that to maintain optimal performance, sports professionals should avoid watching other players in crucial moments of the game, especially when they are likely to be more skilled than their fellows.

This paper appeared in the journal Scientific Reports on November 11 2014.

Full Reference:
“Watching novice action degrades expert motor performance:
Causation between action production and outcome prediction of observed actions by humans”
Tsuyoshi Ikegami & Gowrishankar Ganesh
Scientific Reports, 4, Article number: 6989
http://www.nature.com/srep/2014/141111/srep06989/full/srep06989.html

Link to the press release (in Japanese): https://www.nict.go.jp/press/2014/11/11-1.html