Anticipation and Sport - New Perspectives

Damien Lafont, PhD

damien_lafont@yahoo.fr

A.S.Montferrand Tennis, France

Cognitive control of series of actions:

2008

OutlinesOutlines

Damien Lafont

IntroductionIntroduction Origin of the studyOrigin of the study ObservationsObservations PerspectivesPerspectives

2008

Roger Federer - Backhand / Post-impact

Origin of the study

Damien Lafont© Advantage Tennis - McCarron 2008

Roger Federer - Forehand / Post-impact

Origin of the study

Damien Lafont 2008

ObservationsFederer shows a Federer shows a specific gaze behavior specific gaze behavior

during the hitting phase :during the hitting phase :

Fixation Fixation on the contact zone during on the contact zone during the follow-throughthe follow-through

Unique signature ?Unique signature ?

Damien Lafont 2008

High-speed photo analysis

DataData + 9000 photos + 9000 photos

ATP & WTA tournaments – Top 100ATP & WTA tournaments – Top 100 Backhand & forehand groundstrokesBackhand & forehand groundstrokes Hitting phaseHitting phase

Impact / Post-impactPost-impact

Gaze controlGaze control Involves movements of EYES, HEAD and TRUNK These are coordinated in a way that allows for both These are coordinated in a way that allows for both flexibility of movement and stability of gaze (flexibility of movement and stability of gaze (Land, 2006Land, 2006))

Advantage Tennis - Mike McCarronPablo SanfranciscoVandystadtAFPReutersAssociated PressGetty Images

Damien Lafont 2008

3 hitting profilesBackhand Backhand AND forehand fixation forehand fixation« Total fixation »

Backhand Backhand OR forehand fixation forehand fixation or « intermittent » fixationor « intermittent » fixation

« Partial fixation »

No fixationNo fixation

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« Fog zone »« Fog zone » Different head positionsDifferent head positions

« No fixation »

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« No fixation »

Damien Lafont 2008

« Partial fixation »

© Bakalian - Fedephoto

© AP

Damien Lafont

© Advantage Tennis - McCarron

2008

« Partial fixation »

© AP

© AP

Damien Lafont 2008

« Total fixation »

Damien Lafont 2008

« Total fixation »

Damien Lafont 2008

Total fixation : 10 playersPartial fixation : 36 playersNo fixation

ATP - Top 100ATP ranking 8/20/2007

1. Federer, Nadal, Djokovic, Davydenko, Roddick, Blake, Gonzalez, Robredo, Berdych, Haas, Youzhny, Ljubicic, Gasquet, Canas, Ferrer, Hewitt, Moya, Baghdatis, Murray, Chela, Ferrero, Mathieu, Monaco, Nalbandian, Safin, Nieminen, Tursunov, Almagro, Volandri, Soderling, Starace, Melzer, Karlovic, Stepanek, Verdasco, Hrbaty, Ancic, Kohlschreiber, Andreev, Simon, Clement, Lee, Santoro, Monfils, Gicquel, Montanes, Querrey, Calleri, Becker, Fish, Tipsarevic, Mayer, Hernandez, Eschauer, Rochus, Malisse, Wawrinka, Bjorkman, Del Potro, Massu, Llodra, Lopez, Benneteau, Spadea, Koubek, Ginepri, Russell, Dancevic, Acasuso, Mahut, Delic, Johansson, Vassallo Arguello, Tsonga, Hartfield, Berlocq, Seppi, Roitman, Grosjean, Lapentti, Korolev, Vliegen, Zabaleta, Berrer, Garcia-Lopez, Horna, Bolelli, Guccione, Gulbis, Serra, Luczak, Henman, Kunitsyn, Gabashvili, Haase, Goldstein, Pavel, Pless, Navarro Pastor, Zverev.

Damien Lafont 2008

Top 10

Total fixation: 8 playersPartial fixation: 31 playersNo fixation

ATP - Top 100ATP Ranking 8/25/2008

1.Nadal, Federer, Djokovic, Ferrer, Davydenko, Murray, Nalbandian, Roddick, Blake, Wawrinka, Gonzalez, Gasquet, Verdasco, Karlovic, Robredo, Simon, Del Potro, Almagro, Tsonga, Kiefer, Youzhny, Berdych, Andreev, Cilic, Mathieu, Kohlschreiber, Tursunov, Ancic, Lopez, Stepanek, Seppi, Monaco, Monfils, Soderling, Fish, Schuettler, Nieminen, Llodra, Haas, Gulbis, Gicquel, Moya, Ljubicic, Safin, Tipsarevic, Baghdatis, Bolelli, Melzer, Calleri, Ferrero, Granollers, Canas, Hanescu, Querrey, Hewitt, Benneteau, Schwank, Montanes, Santoro, Ginepri, Darcis, Devilder, Chela, Lapentti, Johansson, Garcia-Lopez, Rochus, Serra, Grosjean, Troicki, Kunitsyn, Lu, Gremelmayr, Navarro, Sela, Starace, Clement, Hernandez, Chardy, Minar, Daniel, Fognini, Mahut, Gabashvili, Bellucci, Guccione, Andujar, Reynolds, Gil, Stakhovsky, Rochus, Volandri, Zverev, Horna, Levine, Haase, Korolev, Berrer, Karanusic.

Damien Lafont 2008

Top 10

Men

Damien Lafont

Grand Slam Champions (since 1999)Grand Slam Champions (since 1999)

Total Federer, Nadal, Hewitt, Ferrero, Kafelnikov

PartialSafin, Kuerten, Moya, Gaudio, Sampras, Costa, Agassi, Johansson

NoIvanisevic, Korda

?

2008

Number ones (since 1997)Number ones (since 1997)

Total Federer, Nadal, Hewitt, Ferrero, Kafelnikov

Partial Safin, Kuerten, Roddick, Sampras, Agassi

NoRafter

Men

Damien Lafont

?

2008

Discussion

Current hitting modelCurrent hitting model« Watch the ball!»« Watch the ball!»

The player should try to watch the ball The player should try to watch the ball throughout its entire flight throughout its entire flight

≠ ≠ OBSERVATIONSOBSERVATIONS

Damien Lafont 2008

A new model ?

Damien Lafont

The best players :

Fix the contact zone after the impact

Switch from the ball to the contact zoneSwitch from the ball to the contact zone

BALLBALL CONTACT ZONECONTACT ZONE

2008

ConclusionThe post-impact « fixation » on the contact zone is a common characteristic of elite players

Men Women?

A key fundamental of the game?A key fundamental of the game?

Damien Lafont 2008

Observations

Damien Lafont

Experts in many tasks show similar fixation stage during the hitting phase

High-level athletes’ performances suggest that there are certainly fundamental benefits in adopting this gaze behaviour jus after contact.

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Effects

Biomechanicals benefits? Mental benefits of the fixation? Cognitive effects?Cognitive effects?

Damien Lafont 2008

Context

Damien Lafont

People’s performance at a given time is influenced by what they plan to do next.

In sport, reading, music reading, typing or driving there are benefits to think and see to think and see ahead.ahead.

2008

Context

Damien Lafont

Table tennis and other ball games : “The secret”:

to know what the ball is going to do as far ahead as possible

• to allow time for the planning and execution of accurate responses.

Players need to determine the future trajectory of the ball and the timing of contact with it (Land and McLeod, 2000).

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Context

Damien Lafont

Ripoll et al. (1988) International table-tennis players anticipate the bounce and made a saccade to a point close to the bounce point.

Land and McLeod (2000)Same thing in cricket, where the ball also bounces before reaching the batsman.

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Context

Damien Lafont

Eye movements in reading are constrained to a linear progression of fixations to the right across the page (Rayner, 1998; Radach et al., 2004).

Similarly, in music reading gaze must move progressively to the right (Land, 2006).

In copy typing, typists of all skill levels attempt to keep the eyes about 1s ahead of the currently typed letter.

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Context

Damien Lafont

Clear relationship between direction of gaze and steering (Land and Lee, 1994; Land, 2006)

drivers spent much of their time looking at the ‘tangent point’ on the up-coming bend.

Many complex tasks require the integration of visual information mainly gained in the first part of the action

Benefit of early anticipationBenefit of early anticipation2008

Context

Damien Lafont

Lafont (2007, 2008)

Top tennis players hold their head still hold their head still when hitting the tennis ball, apparently inhibiting their desire to watch the ball after it leaves the racquet.

By contrast, less accomplished tennis players do not hold their head still when hitting the tennis ball, apparently unable to inhibit their desire to watch the ball after it leaves the racquet.

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Context

Damien Lafont

Vickers (1992, 2004)

In golf, almost all novices follow the ball with their eyes after they hit it ...

... whereas the good player maintains maintains fixation fixation on the same location at the point of impact after the ball is hit

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Context

Damien Lafont

Holding the head still at the time of hitting the ball is likely to permit a more effective hit than allowing the head to turn

Biomechanically, head stability is likely to allow for greater body stability altogether.

Cognitively, holding the head still may heighten the player’s focus on the place and time of contact.

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Now

Damien Lafont

The early part of the movement / ball trajectory (before contact) has been widely studied and is recognized as the most critical.

However, there is much to learn about the way that eye should point in the transition of consecutive actions.

Ex: When anticipation should be initiated ?

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Objectives

Damien Lafont

In many activities : benefits of early preparation

But can our efforts to prepare actually undermine our chances for success?

Can anticipation be detrimental to Can anticipation be detrimental to effective performance in some effective performance in some circumstancescircumstances

2008

?

Hypotheses

Damien Lafont

Visual information Visual information beforebefore contact contact Experts look at points that are particularly informative for the ongoing action

Feedback about the status of the ongoing movement. Information on the ball’s trajectory Planning the ensuing motor response.

WWhat happens hat happens afterafter contact? contact?

2008

Hypotheses

Damien Lafont

First step hypothesisDeprivation of visual feedback on the ball trajectory

doesn’t change the movement accuracy.

≠ Prediction from previous observations People should do better when the ball disappears from view after it is hit than when the ball does not disappear from view after it is hit

At least if the disappearance time is not too long !

Removing visual feedback of post-contact Removing visual feedback of post-contact trajectory will have beneficial effects on trajectory will have beneficial effects on subsequent movements.subsequent movements.

2008

Hypotheses

Damien Lafont

Experts : “dead-eye” gaze

Prevents the inflow of visual inputs that could interfere with the aiming commands set earlier

i.e. the numerous fixations as the ball traverses along its path

More time without interference from other sources.

Limits the number of variables to be controlled.

Limits inaccurate motor outputLimits inaccurate motor output

2008

EEG – Vickers et Crews (2002)EEG – Vickers et Crews (2002) Golf – brain activation and gaze controlGolf – brain activation and gaze control

Damien Lafont 2008

Hypotheses

Hypotheses

Damien Lafont

Natural impulse to anticipate the response of our actions, to evaluate the possible outcomes.

Eye movement even before contact.

To properly see and react, To properly see and react, we must we must abandon our plans and preparations, abandon our plans and preparations, our intents and expectationsour intents and expectations

2008

Hypotheses

Damien Lafont

When subjects can not see the ball ... They receive no concurrent visual feedback about the

progress of the movement. The immediate result of the movement is not available. The attention is not directed to the effect of the action but

to the action itself.

It would allow the players ... to place less value on the outcome of their shots to abandon expectations and intention, to stay on the process

2008... being comfortable with not knowing ...!

Hypotheses

Damien Lafont

Abrams et al. (1990)Visual-feedback processing related to the production of aimed movementsRoles played by different sources of visual feedback

vision of the effector and the target

3 eye-movement hypotheses that describe the coordination of gaze when aiming at near targets.

position-only movement-only movement-plus-position

2008

Hypotheses

Damien Lafont

Alternative hypothesis : A switch from the eye “time-locked” with the ball movement to a stable gaze anchored on the contact point would improve performance.

“Gaze anchoring”

The differences between expert and less skilled performers

the organization of the information chain the simplification of visual input.

2008

Hypotheses

Damien Lafont

How we control the serial order of our behaviors Rosenbaum et al. (2007)

When we engage in behaviors that have distinct elements, the elements of the behaviors must be ordered correctly. Rosenbaum (1991)

Hierarchical treatment of information.

Establishing a constraint hierarchy – a set of prioritized requirements defining the task to be performed - is one of the most important aspects of motion planning (Jax et al., 2003).

Hierarchical organization for Hierarchical organization for behavioral plansbehavioral plans

2008

Hypotheses

Damien Lafont

Land and Furneaux (1997) - ball games: • to know what the ball is going to do as far ahead as possible• time for the planning and execution of accurate responses.

The most relevant information on the ball is gathered during the first part of the trajectory.

Most of studies highlight the potential benefits of early anticipation.

Anticipating Over-Anticipating Over-anticipatinganticipating

2008

Hypotheses

Damien Lafont

Observations : the capture of subsequent cues and evaluation of the upcoming event is not immediately useful after contact.

In specific situations, visual search initiated too early after contact would be even maladaptive for movement.

The period of time after contact when the gaze is stable serves as inhibitory process of too early anticipation process for the next action.

““Time window”Time window”... When anticipation

should be initiated ?2008

Hypotheses

Damien Lafont

Inhibitory control: an important part of performance

Observations: greater capacity for inhibition (or future eye positions)

among top players than among lesser players.

Importance of inhibition in the control Importance of inhibition in the control of movement sequences of movement sequences

2008

Perspectives

Damien Lafont

To gain a more precise picture of the role of visual feedbacks underlying the decision processes

To better understand more fully the contribution of the transition phase between consecutives actions.

In sport: to obtain a more precise idea of what the athletes are required to do, in terms of actions and cognitive processes.

Training purposes.

2008

Other perspectives … Video AnalysisVideo Analysis

Fixation duration?Fixation duration?

Eye-tracker technologyEye-tracker technologyCoupled gaze and body movement measurementsCoupled gaze and body movement measurements

BiomechanicsBiomechanicsEffects on balance, on impact location … Effects on balance, on impact location …

MentalMentalConcentration, control, confidence … Concentration, control, confidence … Pressure?Pressure?

Damien Lafont 2008

Thank you for your attention

Damien Lafont 2008

References

Lafont, D. (2008). Six good reasons to keep your eyes off the ball, ITF Coaching and Sport Science Review, 44.

Lafont, D. (2008). Gaze control during the hitting phase in tennis: a preliminary study, International Journal of Performance Analysis in Sport, 8(1), 85-100.

Lafont, D. (2008). From the ball to the contact zone: Evidence of visual referential switch among elite tennis players, Le tennis dans la société de demain, Dijon, France, April 2008.

Lafont, D. (2007). High-speed photo analysis of top players’ gaze behaviour, Tennis Science and Technology 3, ITF publication, London, 227-233.

Lafont, D. (2007). Towards a new hitting model in tennis, International Journal of Performance Analysis in Sport, 7(3), 104-114.

Lafont, D. (2007). Watch the ball? ITF Coaching and Sport Science Review, 43, p.11.

2008

other perspectives ...

Damien Lafont 2008

Perspectives

Nature of the fixation skill?Nature of the fixation skill? LearnedLearned NaturalNatural ModellingModelling

Damien Lafont

© Tennis Magazine

2008

FOCUS on the

CONTACT ZONE

FOCUS on the BALL

ConcentrationPresentControlConfidence

Outcome focusNo control

Perspectives - Psychology

Ford et al. (2002)

Damien Lafont

Flow&

Zone

2008

Perspectives - Video analysisDuration of the « fixation »Duration of the « fixation »

stroke typesstroke types

Data base – high level tennis playersData base – high level tennis players Jeff CountsJeff Counts

John YandellJohn Yandell

Damien Lafont

1/250 s 1/125 s

1/60 s

2008

The mysterious question of gender difference ...

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Total fixation: 1 player ?!Partial fixation: 18 players

WTA - Top 100WTA Ranking 8/27/20071. Henin, Sharapova, Jankovic, Kuznetsova, Ivanovic, Chakvetadze, Mauresmo, Petrova, Williams, Bartoli, Hantuchova, Schnyder, Dementieva, Williams V., Vaidisova, Safina, Hingis, Golovin, Peer, Bammer, Bondarenko, Li, Safarova, Srebotnik, Schiavone, Garbin, Mirza, Zvonareva, Santangelo, Sugiyama, Szavay, Radwanska, Krajicek, Medina Garrigues, Stosur, Kirilenko, Razzano, Danilidou, Loit, Muller, Azarenka, Dulko, Paszek, Kanepi, Tu, Poutchkova, Peng, Shaughnessy, Nakamura, Vakulenko, Vinci, Morigami, Bondarenko, Dechy, Sequera, Vesnina, Knapp, Dushevina, Likhovtseva, Granville, Rezai, Meusburger, Cibulkova, Kudryavtseva, Govortsova, Chan, Kerber, Pratt, Molik, Shvedova, Bremond, King, Tanasugarn, Osterloh, Dominguez Lino, Camerin, Yan, Craybas, Ruano Pascual, Gallovits, Zakopalova, Harkleroad, Pennetta, Olaru, Poutchek, Wozniacki, Rodionova, Benesova, Kostanic, Dellacqua, Pin, Wozniak, Cohen-Aloro, Bacsinszky, Arn, Cornet, Obzilzer, Amanmuradova, Bychkova, Bardina

Damien Lafont 2008

Women

Damien Lafont

Grand Slam Champion (since 1999)

Total Graf, Henin, Clijters

Partial Seles, V. Williams, Sharapova, Ivanovic

No Mauresmo, Williams S., Kusnetsova, Dementieva, Pierce, Davenport, Hingis, Sanchez

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Women

Damien Lafont

Number ones (since 1997)

Total Henin, Clijters, Graf

Partial Sharapova, V. Williams, Seles

No Mauresmo, S. Williams S., Hingis, Davenport

2008

« Total fixation » - Henin

Damien Lafont

© AFP

2008

« Total fixation » - Graf

Damien Lafont 2008

© Advantage Tennis - McCarron

Example of experimental setting

Damien Lafont 2008

Experiment

Damien Lafont

DesignFocus on the transition phase

• i.e. the interval between two consecutives actions.

Contributions of different visual feedbacks during the phase of early information for movement accuracy

Video-based experimental setting.

To determine whether post-impact visual To determine whether post-impact visual information on ball and target serve any information on ball and target serve any useful purpose for performance and useful purpose for performance and decision making.decision making.

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Experiment

Damien Lafont

Design

Video gameVideo game Open-source (can be modified)

2 experiments2 experiments Visual conditions Task: move a cursor across the scress and hit a

"ball” toward a specified target (joystick)

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Experiment

Damien Lafont

Temporal occlusionIn unconstrained setting (where perceptual information is continuously available) the eyes usually arrive at the target before the initial impulse in a limb movement (Abrams et al., 1990).

The eyes tend to keep track of a dynamic object (the ball)

Occluding part of the post-contact trajectory will force the participants to switch attention from to switch attention from their usual visual pattern.their usual visual pattern.

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Experiment

Damien Lafont

Temporal occlusion2 ball conditions

Visible-ball condition (the control condition) Complete concurrent feedback regarding the progress of

the ball movements.

Ball disappearance Ball disappearance (when the ball contacts the cursor).

Only partial visual information on the post-contact event. Vary how long the ball disappears from view after it is hit

by the cursor (gradually reducing the disappearance time).

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Experiment 1

Damien Lafont 2008

Experiment 2

Damien Lafont 2008

Experiment

Damien Lafont

Variations

2D movements for the cursor.

Disappearance time of the ball after contact.

To increase the speed of the ball.

Target visibility.

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Experiment

Damien Lafont

Variations - from 1D to 2D

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Experiment

Damien Lafont

Variations – Disappearance time

Gradually reduce how long the ball disappears from view after it is hit by the cursor.

It will allow to determinate the limits of the critical period after contact.

Variations – Ball speedThe subjects could be pressured to minimize their movement latency.

Reduce the amount of time available to execute the movement.

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Experiment

Damien Lafont

Variations - Target disappearance

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Experiment

Damien Lafont

Result estimation

Trade-off between facilitation of accurate movement execution and detrimental effects.

Reaction and movement times.Accuracy and speed of each trial.

Exp.1: time to destroy the two lines (i.e. all bricks). Exp.2: 1 point for each ball/target contact.

2008

Experiment

Damien Lafont

Results / Quality of performance ...

1 - No difference in accuracy between movements perform under full and partly visual feedback.

2 - The accuracy of participant decreases

3 - Increase of accuracy Evidence for the potential benefit of a switch

of visual referential in the post-contact phase. Identify the “time window”

2008

?