Stephen F. Austin StateUniversity
Over the past decade different approacheshave been developed for noninvasively studying brain activity. Forexample, positron emission tomography (PET), single photon emissioncomputer tomography (SPECT), and magnetic resonance imaging (MRI)have been more frequently used in research. PET, SPECT, and MRI brainscans were not able to give researchers many of the advantages that afunctional MRI (fMRI) can provide (Moonen, 1995). The advantages ofthe functional MRI include little discomfort, no radiation, clearerspatial and temporal images, and the ability of the examiner toobserve detailed anatomical data about the brain (Moonen, 1995).Therefore, the fMRI can allow researchers to examine the activity ofa human brain with more detail and precision than everbefore.
fMRI allows researchers to examine thepathways and neural connections in the brain. Within the visualsystem of the brain, there are two distinct pathways that help humansprocess information. These are the "what" (ventral) and "where"(dorsal) pathways. Both of these pathways are important in theprocessing of object identification as well as where in the visualspace the object is located. These pathways use cues such as depth,texture, and space (Kraunt, Hart, Soher, & Gordon, 1997).Previous fMRI studies have found that as a stimulus becomes morefamiliar to the participant, there is an enhancement of neuralresponses in the prefrontal cortex. Their study demonstrated that theobject was identified and maintained in the working memory of theparticipant. Simultaneously to identification, there is a reductionof neural response in the parietal and ventral temporal cortices whenthe object is repeated (Jiang, Haxby, Martin, Ungerleider, &Parasuraman, 2000). Object identification is one of the first stepsin processing a moving object.
Other studies have identified additionalways to process moving objects in the visual field. According toSchubotz and Cramon (2001), when a person is confronted with a movingobject, information must be processed in three ways. First is objectinformation; the object must be perceived as a whole unit. Second isspatial information; the direction and distance must be referencedrelative to the body and head. Third is timing information; theobserver must precisely determine the speed of the object to adaptthe observerís own movement. As shown during fMRIs, objectinformation produces a response in the ventrolateral premotor cortex(vPMC) (Schubotz & Cramon, 2001). Spatial information isprocessed in the dorsolateral premotor region. Finally, theprocessing of the timing information takes place in the frontalopercular cortex (Schubotz & Cramon, 2001).
Once a particular object is identified, theperson can attend to a greater amount of detail on the object. Forexample, when a person is asked to attend to a specific property ofan object, such as motion, top-down processing occurs. Top-downprocessing can cause an enhanced neural response to other propertiesof the same object such as depth (OíCraven, Downing, andKanwisher, 1999). When attention is paid to a particular movingobject, an increase in neural response is noticed in V1 and the MTarea of the brain (Watanabe, et al., 1998). While attending to themovement of an object, the brain must also track motion. The visualsystem can track important targets in the following ways. Eyemovements can continually track a specific target, or the eyemovements can focus on the target by saccades, or slight jumps todifferent targets (Culham, et al., 1998).
Previous research has found that there is anincrease in neural activity in the right hemisphere of the brain whena participant is attempting to process the motion of an object(Dieterich, Bucher, Seelos, & Brandt, 1998). According to Perryand Zeki (2000), when processing spatial attention in the visualsystem, the work is distributed unequally across the two hemispheres.They found that if a person has a lesion in the left hemisphere ofthe brain, the participant fails to explore the left side of theirenvironment. In one study participants were given tasks to performwhich examined the part of the brain that processes information eachhand performs. For the left-handed tasks, there was an increase inactivity in the right primary motor cortex and the left cerebellarhemisphere. Right-handed tasks produced an increase in activity inthe left primary motor cortex and the right cerebellar hemisphere(Fink, et al., 2000). This research suggests that if an athlete isright or left handed, a ball coming toward them, which they must hitwith a bat, racket, or foot, will be processed in different areas ofthe brain, according to their dominant hand.
Along with processing the movement of theball in space, the brain must also process the bodyís reactionto the ball coming toward them. Downing, Jiang, Shuman and Kanwisher(2001), have located an area in the brain they have labeled theextrastriate body area, or the EBA. This area, which is located inthe lateral occipitotemporal cortex, is believed to process theappearance of the human body, including the position of oneísown body. This could be particularly useful in team sports where aplayer must be aware of the position of their body in order toconnect with a ball.
Over the last few years, there has been alot of research examining the brain using fMRIs. However, there hasbeen no research studying the processing of information of anathleteís processing of a ball that is used in his/her sport,or other balls they are less familiar with, as well as speed andaccuracy. Furthermore, no research has been done to examine thedifferent ways athletes process this information relative tonon-athletes or athletes from different sports, viewing sportappropriate and nonappropriate ball. The purpose of the presentresearch is to examine if an athlete processes a ballís motionin the same areas of the brain that a non-athlete would use toprocess the same ball, also, if an athlete is as accurate indetermining when the ball would strike them at varying speeds as anon-athlete. It was hypothesized that athletes will use the parietalcortex of the brain to process the motion of their sports ball, buttheir processing will be different from non-athletes processing ofthe same sports balls. It was also hypothesized that an athlete willbe more accurate in determining when their respective ball would hitthem than non-athletes or other athletes of differentsports.
Participants will consist of 60 collegestudents ranging in age from 18 to 24. There will be 30 athletes, (10soccer players, 10 tennis players, and 10 baseball players), as wellas 30 non-athletes. All athletic participants will be recruited fromsign up sheets in the designated sports locker rooms, which will askfor athletes of certain sports; all athletes play their respectivesport at Stephen F. Austin State University. Non-athlete participantswill be recruited from sign up sheets located in the psychologydepartment at Stephen F. Austin State University. Based on the ethniccomposition of Stephen F. Austin Sate University, the ethnic majoritywill be Caucasian followed by African American along with a smallsample of other ethnicityies. Participants will not be compensated inany way; their participation will be completely voluntary.
A functional magnetic resonance imaging(fMRI) machine will be utilized in this experiment. The stimuli usedin this experiment will be three computer-generated 3-D pictures ofsports balls, (tennis ball, soccer ball, and a baseball), shown atvarying speeds, and in the appropriate context. A questionnaire willbe used to obtain participantsí age, ethnicity, and gender aswell as what sports they play or do not play.
Before beginning participants will read aninformed consent form. The participants will participate in the studyone at a time. They will then be given a questionnaire to obtaindemographics information and the sport they play or a confirmationthat the participant does not play a sport. Participants will then bescanned using the fMRI and given a response button to push when theythink the ball will hit them. The participants will then be shown amovie of the three sports balls (soccer, tennis, and baseball). Theball will appear to start 100 feet away from them and come closer.Each participant will receive 10 computer-generated random trials,the order and speed of the balls will be varied.
This study utilized a 4 (tennis player,soccer player, baseball player, non-athlete) X 3 (the type ofsports ball) X 2 (speed of ball) mixed subjects design. The dependentvariables were as follows: location of neural activation and strengthof neural activation, and accuracy of estimated contacttime.
The analysis, to be performed, would be anexamination of the pictures of the brain produced by the fMRI. Also,a mixed ANOVA would be performed to determine the effect on accuracy.The athletes in each sport will perform better on accuracy no matterwhat the speed is in comparision to non-athletes or the athletes ofdifferent sports. This study will not have a main effect between theathlete and type of ball, all athletes scored higher on accuracy thennon-athletes and athletes of different sports. There will be a maineffect between the non-athletes and the sports. The non-athletesperformed worse in all sports than did athletes, even if the sportwas not theirs. The results of this study should be in support of thehypothesis. All of the athletes process their respective sports ballin the parietal cortex of the brain and non-athletes processed allballs differently. The non-athletes process the balls in theposterier region of the brain. This is believed to be what wouldhappen based on previous research. Jiang et al. (2000), found thatthere are two areas in the brain that contribute to the processing offamiliar stimuli. One area signals the object to be identified andthe other signals whether the stimulus has (or has not) previouslybeen seen. Therefore, when the participant is shown the sport ballthat is not their sport, or the non-athlete is shown any of theballs, the brain is signaled that the previous stimuli were notnecessary to process. Then, when the participant is shown theirrespective sports ball, the brain observes it as highly familiar andprocesses it differently than an unfamiliar object. The processing ofhighly familiar objects occurs in the frontal cortex (Jiang, et al.,2000). The non-athlete or the athlete who was attempting to processthe non-familiar ball will show an increase in neural activity in theparietal cortex of the brain (Jiang, et al., 2000).
Also, it is believed that the speed of theball and the accuracy to hit the ball would be processed differentlywhen the participant was attempting to judge their sports ball. Thenon-athletes and the atheletes when judging balls of other sportswould have poorer judgment of the speed and accuracy of when the ballwould strike them. The ability to track the ball is due to the amountof attention the participant paid to the ball, as well as top-downprocessing due to experience. These results are based on the researchdone by Culham et al. (1998). They found that when an object wasattended to the participant showed an increase in neural activity inthe parietal cortex. Furthermore, Culham et al. (1998), determinedthat most of the activity in the parietal cortex happened on an arc,which ran within the parietoccipital junction to thePostCS.
The results of this study indicate thatathletes and non-athletes do process information about a familiarobject differently. The fMRI has shown that athletes processinformation about familiar objects such as their sports ball in theparietal cortex, which also suggests that the processing which occursin the parietal cortex is involved in high-level processes. Theresults of this study would further support the evidence that thedorsal and ventral pathways play an important role in identifying andprocessing familiar and non-familiar objects (Kraunt, et al.,1997).
Further research could be done in severalareas. For example, more athletes involved in different sports mayyield different results. Sports such as pool or hockey may usedifferent areas of the brain since these sports utilize differentskills. Another area of research could examine if the level ofability affects the area of the brain. Other experimenters could alsoexamine if the athlete needs to pay more attention to the object ifthe athlete does not play the sport frequently. A third area ofresearch may examine the processing of the ball in theparticipantís periphery of vision. Some athletes do not needto pay attention to the object to strike the ball, and only glance atthe ball in their peripheral vision, for example soccerplayers.
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