The advantage of being left-handedIn interactive sports

Norbert,H. (2009)Attention, Perception, & Psycholophysics, 71(7), 1641-1648.

• 證明左撇子在互動式運動具有優勢是因negative perceptual frequency effects 。

• 左撇子比例約為 10%-13% ，卻在互動式運動表現突出， (boxing,) 以網球為例。

• TOP 10 比例 male, 24.06%; female, 11.80% 。

• 大滿貫決賽 male, 22.27%; female, 18.75% 。

• 解釋左撇子優勢的理論• Earlier Explanations:1.Innate superiority hypothesis. (Geschwind and Gal- aburda 1987)2.Strategic advantage hypothesis. (Grouios, 2004; Grouios, Koidou,

Tsorbatzouidis, & Alexandris, 2002)

• Perception of Human Movements:1.Focus of orientation in the perception of

humanmovements. ( Pollick, Lestou, Ryu, & Cho, 2002)2. Side-specific perception of human

movements in sport. ( McMorris and Colenso 1996)

• Earlier Explanations:

• 1.Innate superiority hypothesis. (Geschwind and Gal- aburda 1987)

• 2.Strategic advantage hypothesis. (Grouios, 2004; Grouios, Koidou, Tsorbatzouidis, &

Alexandris, 2002)

Earlier Explanations:

• 1.Innate superiority hypothesis: Left-handers possess a neuropsychological

advantage. • 2.Strategic advantage hypothesis. They have a strategic or tactical advantage .

• Perception of Human Movements:

• 1.Focus of orientation in the perception of humanmovements.

( Pollick, Lestou, Ryu, & Cho, 2002)

• 2. Side-specific perception of human movements in sport.

( McMorris and Colenso 1996)

Perception of Human Movements

• 1.Focus of orientation in the perception of humanmovements.

-These studies assume that this sensitivity in distinguishing between different human movements depends on visual experience.

Perception of Human Movements

• 2. Side-specific perception of human movements in sport.

- This strong dependence on both visual experience and the horizontal orientation, it is proposed the sport-type-specific ability with the left hand is less well developed.

Perception of Human Movements

• Negative perceptual frequency effects hypothesis.

-The lower frequency with which athletes in interactive sports are confronted with movements by left-handed opponents.

Method

• Participants:

-108 males, 54 right-handers (RH) and 54 left-handers selected with the German version of the EHI .

-Divided into three groups by experience.

(experts,intermediates,novices)

Method

• Test Procedure

-The participants viewed videotaped sequences of tennis strokes on a laptop computer and had to predict the direction and depth of each stroke.

videotaped sequences

• Two left-handed and two right-handed.

• Twelve strokes (six groundstrokes, four volleys, and two serves) were recorded from each player. 加上鏡射呈現

• Total 96video clips. 受試者對於球的落點做預測，再以 radial error 計算誤差。

• federer.vs.nadal.wimbledon.2006.

• federer.vs.nadal.wimbledon.2007.

• federer.vs.roddick.wimbledon.2009.

Method

3 (group) × 2 (handedness of participant) × 2 (playing hand in video) × 2 (initial handedness of player in video)

mixed ANOVA.

Results

Results

Results

Discussion

• The ability to discriminate left-handed movement patterns is less well developed than that for right-handed movement patterns.

Discussion

• Does the Participants’ own Handedness exert an Influence?

• 以 Mirror neurons 來看 :

• A left-hander might be easier for a left-hander to discriminate than for a right-hander.

• 結果並非如此

Discussion

• Do the Movement Patterns of left-Handers Simply Mirror the Movements of Right-Handers?

• There should also be no interaction between the playing hand in video and initial handedness of player in video variables.

Discussion

• Negative perceptual frequency effect (see Faurie & Ray-mond, 2005) and can be assigned to the set of strategic advantages of left-handers in sport.

Discussion

• Automated decision preferences that are

generalized incorrectly from tactical play against right-handers.