motor performance of children with mild mental ... mental disabilities after using mental imagery...

ADAPTED PHYSICAL ACTIVITY QUARTERLY, 1997,14,119-130 0 1997 Human Kinetics Publishers, Inc.

Motor Performance of Children With Mild Mental Disabilities After

Using Mental Imagery

Doris Pogue Screws University of New Orleans

Paul R. Surburg Indiana University

In order to improve motor performance, mental imagery procedures have evolved over the years with nondisabled subjects. Studies re- searching the concept of using mental imagery with special populations (Surburg, & Stumpner, 1987; Surburg, 1991; Surburg, Porretta, & Sutlive, 1995) are very few in number. This study examined the efficacy of using mental imagery in developing skill on a motorically oriented task (pursuit rotor) and a cognitively oriented task (peg board) on middle school students with mild mental disabilities (MMD). Thirty subjects were assigned randomly to a physical, imagery, or no-practice control group to perform either a peg board or pursuit rotor task. For each motor task, there was a pretest followed by appropriate treatment regime and a posttest session. The dependent variables were the number of pegs placed in appropriate order for the peg board task and time on target for the pursuit rotor task. Results were that imagery practice enhanced the motor performance of children with MMD on both the peg board (cognitively oriented task) and pursuit rotor (motorically oriented task).

The appropriate education of children who are mentally disabled in our soci- ety, and the escalating cost of their education, has been an increasing concern to parents, educators, and psychologists. Adapted physical educators are continually searching and investigating new theories and concepts to enhance motor performance. Mental imagery is one technique that has shown to enhance motor performance in individuals without disabilities (Weinberg, 1982; Kohl, Ellis, & Roenker, 1992).

Imagery practice (Kohl, Ellis, & Roenker, 1992), mental rehearsal (Epstein, 1980), and mental practice (Feltz & Landers, 1983) are terms used to describe the same type of practice. Magill (1985, p. 384) referred to mental imagery as cognitive rehearsal of a physical skill in the absence of overt, physical movement;

Doris Pogue Screws is with the Department of Human Performance and Health Pro- motion, University of New Orleans, New Orleans, LA 70148. Paul R. Surburg is with the Department of Kinesiology, Indiana University, Bloomington, IN 47407.

120 Screws and Surburg

Richardson (1967a, p. 95) described mental imagery as "symbolic rehearsal of a physical activity in the absence of any gross muscular movements."

With nondisabled subjects, imagery studies have been conducted primarily with college age or adult volunteers (Epstein, 1980; Kohl & Roenker, 1980; Ryan & Simons, 1981; Surburg, 1968, 1976). By contrast, relatively few studies have incorporated high school subjects (Corbin, 1967; Bums, 1962; Clark, 1960; Murphy, 1977) and an even lesser number of investigations have used middle school or elementary aged persons in imagery research (Johnson, 1967; Whitehill, 1965). A perusal of imagery practice studies revealed a hierarchy of effectiveness with either physical or physical and imagery practice as the most effective technique (Ryan & Simon, 1983; Wrisberg & Ragsdale, 1979; Koslow, 1987; Surburg, 1976), followed by exclusive use of imagery practice and, hstly, the no-practice or control condition (Rawlings, Rawling, Chen, & Yilk, 1972; Kohl & Roenker, 1980).

Few studies have investigated the concept of mental imagery with special populations. Lebrato and Ellis (1974) found this technique to be effective with individuals who were mentally disabled in a cognitive learning situation. Groden and Cautela (1984) were successful using covert reinforcement and covert modeling imagery procedures to reduce aberrant behaviors in the classroom. Using children with mental disabilities and preschool children with learning disabilities, Greeson (1986) investigated task-related effects of modeling-based mental imagery training in a series of learning tasks. With both populations, positive effects of this imaging training technique were found to occur for all learning tasks.

In the motor domain, Reid (1980) examined the role of overt and covert rehearsal in short-term memory situations. Covert rehearsal and practice are terms that have been used in imagery research (Corbin, 1967). Reid reported no evidence of effective spontaneous covert rehearsal with elementary students who were mentally disabled. Surburg (1991) used imagery practice to facilitate the preparation of adolescents with mild mental retardation to perform a motor task. Subjects performed a response-type task that included reaction time and movement time components, with catch trials used to manipulate the preparation levels. Results suggested that with marked preparation decrements, imagery practice facilitated the execution of the reaction time components and, under certain conditions, imagery practice also helped performance of the movement time component. Surburg, Porretta, and Sutlive (1995) examined the role of supplementary practice in the form of imagery practice on the performance of a throwing task with students who were mildly mentally disabled (MMD). Results revealed the efficacy of imagery practice as a means to improve motor performance.

Reviewers of the mental imagery literature have indicated that, under certain circumstances, mental imagery appears to be an effective means of enhancing the performance of motor tasks in nondisabled individuals (Corbin, 1972; Richardson, 1967b; Weinberg, 1982). An interesting synthesis and meta-analysis of this literature was conducted by Feltz and Landers (1983). Based on their analysis, these researchers developed four propositions.

They were:

1. Mental imagery effects are basically associated with cognitive-symbolic rather than motor component of the task.

2. Mental imagery effects are found in early and later stages of learning and may be task specific.

Mental Imagery and Motor Performance 121

3. It is uncertain that low-gain neuromuscular patterns during mental imagery are identical to those patterns produced during actual performance.

4. Mental imagery assists the performer in psychologically preparing for the skill to be performed (Feltz & Landers, 1983, pp. 45-50).

Proposition I was based on the finding that the effect size of the cognitively oriented tasks were significantly larger than the motor-oriented tasks. Earlier research supports this proposition. Ryan and Simons (1981), Wrisberg and Ragsdale (1979), and Minas (1978) noted that mental practice enhanced motor performance on cognitive tasks (block test, dial-a-maze) but did not affect motor tasks that were low in cognitive or symbolic elements (stabilometer). The concept of Proposition 1 served as the theoretical construct for this study.

No studies have used imagery techniques with both cognitive and motor- oriented tasks with individuals who have any type of disability. Using imagery practice in conjunction with physical practice could provide adapted physical educators with a means for improving motor performance of children with MMD. The application of mental imagery in the adapted physical education setting may facilitate an opportunity for individuals with MMD to think through a motor task and direct their attention to the cues and stimuli needed to produce quality movement. Although there have been many studies investigating the effect of mental imagery on motor task execution for individuals without disabilities, there have been very few studies specifically studying motor performance of individuals who are mentally disabled with this technique. At this juncture in time, no studies have determined if imagery techniques are an effective means for improving motor performance of middle school children with MMD. By investigating cognitive versus motor-oriented tasks, we may be provided with a better understanding of how imagery works with persons who are mentally disabled.

The purpose of the study was to determine the efficacy of employing imagery techniques on children with mild mental disabilities to improve performance on a cognitively oriented task (peg board) and a motorically oriented task (pursuit rotor). The working hypotheses of this study were:

1. The physical practice groups would exhibit significant improvement on skill performance of both tasks;

2. The control groups would not exhibit significant improvement in skill performance of either task; and

3. The imagery practice group would exhibit significant improvement on skill performance with the cognitively oriented task.

Method

Subjects

Subjects included 30 middle school volunteers with MMD, ranging in age from 11 to 13 years old (mean = 12.5), who were from a rural school in Alabama. They were identified as MMD by the Special Education Director with 1.Q.s ranging from 50 to 70 on the Wechsler Intelligence Scale for Children-Revised, and classi- fied as children who were MMD according to the State of Alabama Department of Education criteria. These subjects attended physical education and science classes


with their nondisabled peers and remained in the special education classroom for other classes. The sample had no history of auditory, visual, orthopedic, or behav- ior impairments and were not taking prescribed medication that would hinder motor performance.

Instruments

Cognitive-Oriented Task-Peg Board. The peg board was developed by Perry (1939) as a cognitively oriented motor task for investigating factors that affect motor performance. It was a tray 56 cm x 33 cm x .64 cm consisting of three compartments. In the center compartment (3 1 cm x 39 cm x 2 cm) were 30 square blocks 6 cm x 6 cm x 2 cm. e if teen blocks were painted red and had square holes in the center 1 cm x 1 cm; 15 blocks were painted blue and had round holes in the center 1 cm in diameter. The blocks bore numbers from 1 to 30. The square-holed red blocks carried the even numbers and the round-holed blue blocks carried the odd numbers. The blocks were arranged in an order to eliminate the possibility of having even numbers located by even numbers and odd numbers located by odd numbers. This ordering ensured the alternation of red and blue in a checkerboard pattern and also prevented the sequences that might occur in a random arrangement.

In the left hand compartment (3 1 cm x 3 cm x 2 cm) were 15 square red pegs 7 cm x 1 cm placed so that the subject may reach them easily with the left hand. In the right hand compartment (3 1 cm x 3 cm x 2 cm) were 15 round blue pegs 7 cm x 1 cm placed so that the subject may reach them easily with the right hand. A stop watch was used to time each trial. The score was the number of pegs placed in the blocks in the proper arrangement.

Motoric-Oriented Task-Pursuit Rotor. The Lafayette Pursuit Rotor fre- quently has been used by investigators to assess the effect of experimental factors on motor performance (Kohl & Roenker, 1980,1983; Rawlings & Rawlings, 1974; Smyth, 1975; Horgan, 1980, 1982; Surburg, 1976; Rawlings et al., 1972). Using the pursuit rotor to assess motor performance of individuals with MMD, Horgan (1982, 1980) obtained reliability coefficients of .92 and .94, respectively.

The Lafayette Pursuit Rotor used in this study was model 30013. This in- strument consisted of a rotating light below a glass cover set at 45 rpm. Selection of 45 rpm was based on pilot data and the works of Horgan (1980, 1982). A stylus for tracking this rotating target was part of this device. An interval timer, model number 50013 was used to regulate the duration of each trial. A chronoscope, model number 54035, was integrated into the system for measuring total timebn target. In order to reduce resistance, the glass cover over the rotating light and tip of the stylus were cleaned after being used by each subject. The score was time on target measures (.01 seconds).

Procedure

Prior to administering the experimental conditions, a pretest was given to assess the motor performance of the subjects. Fifteen subjects were randomly assigned to perform the peg board task and 15 were assigned to the pursuit rotor task. The peg board task was selected to determine the motor performance level for the cognitive task group and the pursuit rotor task for the motoric task group. Before administering the task to the subjects in the format of a game, the nature of the game and


instructions for the performance of the task were explained and demonstrated. Subjects were afforded opportunities to ask questions during and after the demon- stration. Subjects were given five practice trials on either the pursuit rotor or peg board game to insure that they understood the procedures before the pretest was given.

On the first practice trial for the peg board task group, subjects were instructed to take a round blue peg (odd numbers) in their right hand and place it in the block numbered 1, then take a square red peg in their left hand and place it in block number 2, and continue alternating in order until all the blocks were filled. After the first trial, the pegs were removed from the board and replaced in the proper trays. Subjects were then given four additional practice trials of 30 seconds. Standardized instructions were provided to all subjects and repeated until the subjects could show a complete understanding. Subjects were afforded opportunities to ask questions during and after standardized instructions.

Following completion of the practice trials, the pretest was administered. The pretest consisted of having subjects alternate their right and left hands to place pegs in the correct order as fast as possible for 20 trials of 30 seconds with 30 seconds of rest between each trial. The score for each trial was the number of pegs placed in the blocks in the proper order after each trial.

On the practice trials for the pursuit rotor group, subjects were instructed to practice tracking the rotating light with a stylus using their preferred hand for 30 seconds. Following the first practice trial, subjects were given four additional trials of 30 seconds. Standardized instructions were provided to all subjects and repeated until they could demonstrate a complete understanding. Subjects were afforded opportunities to ask questions during and after the standardized instructions to insure total com- prehension.

After this orientation period, the pretest was administered. The pretest consisted of having subjects track a rotating light with a stylus using their preferred hand for 20 trials of 30 seconds, with 30 seconds of rest between each trial.

After the pretest, five subjects within each task group were randomly assigned to a physical practice, imagery practice, or no-practice group (control group). A pilot study was conducted to determine the appropriate sample size needed for an investigation of this nature. The first step was to test five subjects and calculate a power statistic. These data also would be used to estimate an appropriate sample size. The calculated power statistic was .89 which was limited to main effects (Keppel, 1982). It was apparent that for the nature of this task, cell sizes of five would be appropriate. The conditions for each of the three groups were structured to be very similar for each motor task. The physical practice groups practiced 20 trials on either the peg board or pursuit rotor game for eight sessions. These sessions were administered 5 days a week until the prescribed number of sessions were completed. Subjects performed their assigned task (pursuit rotor or peg board) for 30 seconds, and during their rest period of 30 seconds after each trial, con- structed geometric shapes on a Geoboard.

Before the imagery practice groups mentally practiced their assigned task, they were provided an imagery practice orientation. During the imagery practice orientation, the investigator discussed the meaning of imagery practice and explained how to use imagery practice for motor task enhancement. Subjects also were given imagery practice activities to acquaint them with imagery practice procedures.'


In order to control for social interaction, a control group was part of the experimental design. Total time the control subjects interacted with the researcher was structured to be 164 minutes, which was the approximate time spent with the experimental groups. Also, the social quality of the control groups was the same as the mental and physical practice groups.

The no-practice or control groups spent the same amount of time in the experimental setting as did the other experimental groups. Subjects performed one warm up trial of 30 seconds on their assigned task (pursuit rotor or peg board), then 20 minutes of making different geometric shapes on a Geoboard for eight practice sessions, 5 days a week, until the prescribed number of sessions were completed.

A posttest was given after eight practice sessions in order to measure the performance of the groups after the treatment conditions. The procedures used in the posttest were the same as those used in the pretest.

Data Analysis

Time on target for the pursuit rotor task and number of pegs placed correctly for the peg board task were recorded on Trials 1 to 20 and were dependent measures. From the analysis of pilot data, it was determined to use Trials 11 to 20 of the 20 trials of the pretest and posttest. This was based on evaluating blocks of trials for reliability and consistency indices. To analyze the data, a 3 (group) x 2 (test) x 10 (trial) ANOVA with repeated measures on two factors as used with both the peg board and pursuit rotor groups. The .05 level of significance was selected.

The intraclass correlation technique was used for estimating the reliability of tests. The reliability coefficients for the pursuit rotor task ranged from .86 to .95 on the pretest for the three groups, and from .88 to .92 on the posttest. The reliability coefficients for the peg board task ranged from .96 to .98 on the pretest, and from .90 to .98 for the three groups on the posttest.

Results

Peg Board Task

Significant main effects for the peg board task were found for group, F(2,12) = 8 . 4 1 , ~ < .05, test, F(1,12) = 7 1 . 3 9 , ~ < .05, and trial, F(9,108) = 4 . 6 5 , ~ < .05. A significant Test X Group interaction was found, F(2,12) = 1 4 . 9 5 , ~ < .05. Post hoc analyses of this interaction using simple main effects analyses (Keppel, 1982) revealed a significant difference between pretest and posttest for the imagery practice group, a significant difference between pretest and posttest for the physical practice group, no significant difference between pretest and posttest for the no- practice group. No significant differences were found among imagery practice, physical practice, and no-practice groups on the pretest, but a significant difference was found among imagery practice, physical practice, and no-practice groups on the posttest (Table 1). Results of the Tukey post hoc test (Keppel, 1982) was that the physical practice group performed significantly better than the imagery practice and no-practice group (control) on the posttest. The imagery practice group performed significantly better than the no-practice group.

Mental lmage~y and Motor Performance

Table 1 Means and SDs of Performance Scores on Pretest and Posttest for Practice Groups on the Peg Board

Pretest Posttest

n M SD M SD

Imagery practice 5 15.46 3.52 21.04 3.49 Physical practice 5 15.44 5.06 28.66 1.67 No practice 5 13.44 3.46 14.78 2.66

Note. Maximum score for each group = 30; minimum score for each group = 1.

Table 2 Means and SDs of Pursuit Rotor Performance Scores on the Pretest and Posttest for the Practice Groups

Pretest Posttest

n M SD M SD

Imagery practice 5 14.70 2.32 16.56 3.72 Physical practice 5 12.65 2.89 19.64 2.66 No practice 5 13.14 4.37 14.55 3.59 - - - - - - -

Note. Score for each group in seconds.

Pursuit Rotor Task

A significant main effect was found for test, F(1,12) = 48.19,~ < .05, and a significant Test X Group interaction F(2,12) = 13.23, p < .05. Post hoc analyses of this interaction using simple main effect analyses (Keppel, 1982) revealed no significant difference between the pretest and posttest for the no-practice group, but a significant difference between the pretest and posttest for the physical practice group and imagery practice groups were found (Table 2). No significant differences were evident among the imagery practice, physical practice, and no-practice groups on the pretest, but a significant difference was found among the imagery practice, physical practice, and no-practice groups on the posttest. Analysis of the group effect with the Tukey test (Keppel, 1982) revealed that the only significant difference was between the physical practice and no-practice group on the posttest.

Discussion

The primary objective for the study was to determine the efficiency of employing imagery techniques on middle school children with MMD to improve performance on a motorically oriented task (pursuit rotor) and cognitively oriented task (peg


board). The investigation found that the physical practice groups exhibited significant improvement as measured by pretest to posttest scores on skill performance on both the peg board and pursuit rotor tasks. These results corroborate Hypoth- esis 1 of the study which states that the physical practice groups would exhibit significant improvement on skill performance of both tasks.

In middle school children with MMD who mentally imagined the pursuit rotor, a motorically oriented task exhibited significantly superior performance from pretest to posttest. No significant difference was found between the two practice groups on the posttest. This finding indicates that the subjects in the imagery practice group were able to use mental processing to improve their motor performance on the pursuit rotor, a task considered to have few symbolic components. Rawlings et al. (1972) and Oxedine (1969) also found that imagery practice facilitated motor performance of the pursuit rotor, a motoric-oriented task. Even though the pursuit rotor task was low in symbolic components, the imagery practice group of children with MMD were able to mentally rehearse the pursuit rotor task and perform as well as the physical practice group.

These findings and the literature on the effects of imagery practice on physical skill performance of motoric-oriented tasks were not completely mutually sup- portive. Morrisett (1956) found no significant differences among the physical practice, imagery practice, and no-practice groups of children without disabilities on the Santa Ana Finger Dexterity Test. Minas (1978) found that children without disabilities who used imagery practice were superior to both the physical practice and no-practice groups on throwing balls into small bins in a particular sequence. Other research studies involving subjects without disabilities found that there was no significant difference in performance between subjects who received imagery practice and those receiving no practice, and physical practice was significantly superior to both conditions (Ryan & Simons, 1983; Wrisberg & Ragsdale, 1979). The physical practice group in this study was only significantly superior in performance to the no-practice group, and imagery practice was as effective as physical practice as measured by pretest to posttest improvement.

The motor performance of subjects who physically practiced the peg board, a cognitively oriented task, was significantly superior to the children who used imagery practice and those who had no practice. The finding was in agreement with Ryan and Simons (1981, 1983) who also found physical practice to improve motor perfonnance on cognitive tasks with subjects without disabilities. The improvement in motor performance from pretest to posttest by the physical practice group may be attributed to the amount of practice subjects had on the peg board task. Magill (1985, p. 368) maintained that the amount of practice on a skill af- fects a person's motor performance. It is apparent from this significant finding that the amount of physical practice on the peg board task was adequate enough to improve motor performance.

There was no significant difference in motor performance from pretest to posttest on either the peg board (cognitive task) or pursuit rotor (motoric task) for the no-practice, or control groups. The results substantiate Hypothesis 2 of the study which states that the control groups would not exhibit significant improvement in skill performance of either task. The findings concur with past imagery and physical practice investigations which found that without some form of practice intervention there was no pre/post perfonnance change (Minas, 1978; Ryan & Simon, 1983). Additionally, this supports theories that state there can be no im-

lental Imagery and Motor Performance 1 27

rovement in motor performance without mental or physical practice (Schmidt, 975; Sackett, 1935). Children with MMD, who did not practice the pegboard or wrsuit rotor, physically or mentally were unable to attend to the appropriate cues o successfulIy improve motor performance.

There was significant improvement in motor performance with subjects in the imagery practice group on the peg board. The results confirm Hypothesis 3 of the study which states that the imagery practice group would exhibit improvement on skill performance with the cognitively oriented task. Investigators (Minas, 1978; Koslow, 1987; Wrisberg & Ragsdale, 1979) found with nondisabled subjects that imagery practice on cognitive or symbolic tasks such as finger maze, blocks test, mirror drawing, and sequence learning improved motor performance, and imagery practice was better than no practice at all. This symbolic learning effect was strongly supported by Feltz and Landers (1983) meta-analysis of 60 mental practice studies. Results of the current study indicate that imagery practice was used effectively by children with MMD to improve their motor performance.

Analysis of percent change in performance scores from the pretest and posttest of the imagery practice group for the cognitive peg board task (36.09%), and motoric pursuit rotor task (12.65%) revealed that imagery practice had the greatest influence on motor skill performance of middle school children who performed the cognitive task. This finding supports the work of Ryan and Simons (1981), Smyth (1975), Wrisberg and Ragsdale (1979), and Perry (1939) who discovered on individuals without disabilities that imagery practice seems more effective when applied to the perfomiance and learning of a highly cognitive motor task.

It may be postulated that imagery practice techniques facilitated an opportunity for children with MMD in both imagery practice groups to think through the motor task and develop a practice loop (Schmidt, 1988). Thinking through the task may permit both imagery groups to attend to the critical cues of the task, empha- size the cognitive components and group-related information about the task, which allows the learner to identify a feasible action plan. The greater percentage in improvement of the peg board imagery group (36.09%) compared to the pursuit rotor imagery group (12.65%) suggests that the imagery group performing the more cognitive-oriented motor task was able to develop a more effective practice loop by ruling out inappropriate courses of action. This finding supports Feltz and Lander's (1983) Proposition 1 "mental imagery effects are basically associated with cognitive-symbolic rather than motor components of the task" (p. 45).

While the results of this study closely parallel those reported by Feltz and Landers (1983) for the general population, future studies with subjects who are disabled also should include a "manipulation check" during the mental imagery practice sessions. During the check, subjects should be able to express their thought processes so as to give assurance that a "practice loop" is being followed during practice (Schmidt, 198Q2

In conclusion, imagery practice appears to be a viable motor skill improvement technique for skills high (peg board) and low (pursuit rotor) in cognitive symbolic components. This study provides evidence that children with MMD may use imagery techniques to facilitate motor task performance. Hopefully, this study will act as a catalyst to stimulate other investigations. The value of imagery practice with different mental and physical ages of individuals with mental disabilities warrants study as well as the value of various instructional strategies such as con- textual interference. As future studies are conducted, researchers must continue to

128 Screws and SurLx

address the issue of social interaction and continue to devise ways to preclude ar possible confoundment.

i References

- I Burns, P.L. (1962). The effect of physical practice, mental practice, and mental-physicci practice on the development of a motor skill. Unpublished master's thesis, The Penn sylvania State University.

Clark, L.V. (1960). Effect of mental practice on the development of a certain motor skill

i Research Quarterly, 31,560-569.

Corbin, C.B. (1967). Effects of mental practice on skill development after controlled practice. Research Quarterly, 38,534-538.

- Corbin, C.B. (1972). Mental practice. In W.P. Morgan (Ed.), Ergogenics aids and muscular pelformance (pp. 94-1 18). New York: Academic Press.

1 Denis, M. (1985). Visual imagery and the use of mental practice in the development of motor skills. Canadian Journal of Applied Sport Sciences, 10,4S-16s.

Epstein, M.L. (1980). The relationship of mental imagery and mental rehearsal to perfor-

1 mance of a motor task. Journal of Sport Psychology, 2,211-220. Fela, D.L., & Landers, D.M. (1983). The effects of mental practice on motor skill learning

and performance: A mental-analysis. Journal of Sport Psychology, 5,25-57.

1 Greeson, L. (1986). Modeling and mental imagery use by multiply handicapped and learn-

ing disabled preschool children. Psychology in the School. 23,82-86. Groden, J., & Cautela, J. (1984). Use of imagery procedures with students labeled "train-

able retarded." Psychological Reports, 54,595-605.

w

i

Hall, C.R., & Fishburne, G.J. (1992). Imagery and the acquisition of motor skills. Cana- dian Journal of Sport Sciences, 17, 19-27.

Hoover, J.H., & Wade, M.G. (1985). Motor learning theory and mentally retarded individuals: A historical review. Adapted Physical Activity Quarterly, 2,228-252.

Horgan, J.S. (1980). Pursuit rotor learning of mildly retarded children under supplementary feedback conditions. Perceptual and Motor Skills, 50, 1219-1228.

Horgan, J.S. (1982). Comparison of mildly mentally retarded and nonretarded children on a rotary pursuit task under optimal task conditions. American Journal of Mental Defi- ciency, 87,316-324.

Johnson, B.L. (1967). An examination of some factors which might be related to eflective utilization of mental practice in learning a gross motor skill. Unpublished master's thesis, University of Oregon, Eugene, OR.

Kelso, J.A., Goodman, D., Stamm, C.L., &Hayes, C. (1979). Movement coding andmemory in retarded children. American Journal of Mental Deficiency, 83,601-61 1.

Keppel, G. (1982). Design and analysis: A researcher's handbook (2nd ed.) Englewood Cliffs, NJ: Prentice-Hall, Inc.

Kohl, R.M., Ellis, S.D., & Roenker, D.L. (1992). Alternating actual and imagery practice: Preliminary theoretical considerations. Research Quarterly for Exercise and Sport, 63,162-170.

1980). Bilateral transfer as a function of mental imagery. Jour-

83). Mechanism involvement during skill imagery. Journal of

visual-spatial mental imagery as-factom -a

. Sex RoZes, 17,521-527.


Lebrato, M.T., & Ellis, N.R. (1974). Imagery mediation in pair-associated learning by retarded and nonretarded subjects. American Journal of Mental Dejiciency, 78,704-713.

MagilI, R.A. (1985). Motor learning concepts and applications. Dubuque, IA: William C. Brown.

Minas, S.C. (1978). Mental practice of a complex perceptual-motor skill. Journal of Human Movement, 4,102-107.

Morrisett, L.N. (1956). The role of implicitpractice in learning. Unpublished doctoral disser- tation, Yale University, New Haven, CT.

Murphy, T.J. (1977). The effects of mental warm-up on jump shooting accuracy among selected boys'high school basketballplayers. Unpublished master's thesis, South Dakota State University, Brookings, SD.

Oxendine, J.B. (1969). Effect of mental and physical practice on the learning of three motor skills. Research Quarterly, 40,763-775.

Perry, H.M. (1939). The relative efficiency of actual and imaginary practice in five selective tasks. Archives of Psychology, 34,5-75.

Rawlings, E.I., & Rawling, I.L. (1974). Rotary pursuit tracking following mental rehearsal as a function of vocabulary control of visual imagery. Perceptual and Motor Skills, 38, 302.

Rawlings, E.I., Rawlings, I.L., Chen, S., &Yilk, M.D. (1972). The facilitating effects of mental rehearsal in the acquisition of r o w pursuit tracking. Psychonomic Science, 26,71-73.

Reid, G. (1980). Overt and covert rehearsal in short-term motor memory of mentally retarded and nonretarded persons. American Journal of Mental Deficiency, 85,69-77.

Richardson, A. (1967a). Mental practice: A review and discussion, Part I. Research Quarterly, 38,95-105.

Richardson, A. (1967b). Mental practice: Areview and discussion, Part 11. Research Quarterly, 38,263-273.

Ryan, D.E., & Simons, J. (1981). Cognitive demands imagery, and frequency of mental rehearsal as factors influencing acquisition of motor skills. Joumal of Sport Psychology, 3,35-45.

Ryan, D.E., & Simons, J. (1983). What is learned in mental practice of motor skills: A test of the cognitive motor hypothesis. Journal of Sport Psychology, 5,419-426.

Sackett, R.S. (1935). The relationship between amount of symbolic rehearsal and retention of amaze habit. Journal of General Psychology, 13,113-128.

Schmidt, R.A. (1975). A schema theory of discrete motor skill learning. Psychological Review, 82,225-260.

Schmidt R.A. (1988). Motor control and leaming. Champaign, IL: Human Kinetic Publish- ing, Inc.

Smyth, M.M. (1975). The role of mental practice in skill acquisition. Journal ofMotor Be&- ior, 3,199-206.

Surburg, P.R. (1968). Audio, visual, and audio-visual instruction with mental practice in developing the forehand tennis drive. Research Quarterly, 39,728-734.

Surburg, P.R. (1976). Aging and effect of physical-mental practice upon acquisition and retention of a motor skill. Journal of Gerontology, 3,64-67.

Surburg, P.R. (1991). Preparation process facilitation of a motor task through imagery practice with adolescents who have mental retardation. American Joumal on Mental Retarda- tion, 95,428-434.

Surburg, P.R., & Stumpner, S.S. (1987). Use of imageiyprocedures with mildly mentally handicapped persons. Paper presented at the meeting of the American Alliance of Health, Physical Education, Research, and Dance. Las Vegas, NV.

.uogsaKKns sq 303 JaMayaz snourLuow w wy] 01 aTI ppoM sloylne au, .~sanba~ uodn sloylne ayl uroy aIqe1FAe art! smafqns ayl 01 suogewldxa 3gyads a-,

'80Z-IOZ 'S 'sa'pn1S iuawanoM znnun~Jo latunof 'sllqs JO~OUI 30 psnaqai @)uaur ayl ut slo13ed :fanal mg3e.1d pw pueurap a~gpBo3 '(6~61) 'XW 'a@ps%?x 18 ''~3 '~I~~SUM

.uo%a.xo $0 Ifirs~a~!un *uo!Ietrass!p 1e.10130~ paqsyqndun .sll?ys JOJW sso~8io uo?yua~a.t puz? 8u?wvq s, uarppzp uo a3y3v~d ~vluaw So sl3a& azjL '(~961) '&K 'lI!qa~!q&

'£1~-561 'cc '1sanD .anbgu3 pue Ma?aal .b. :a3ueuuopad lojou~ pup sal%a)~as uogenda~d Ieluaur uaaMlaq dgsuoge~a~ aqL '(2861) 'x 'S~aqura~

'E8-LL '9 '23~f3vJd OJU? k02l.f~ :Sll!qs l010~ '~UFSS~~

-old uopeuuoju~ jo uow3!ldde qKnoq1 uog!s!nb3e ~fqs Kuy~uequ~ '(2861) 'v.8 'u!&n~ .Lzz-LIz '1 '@a~m?o &?~?~3~/~)3ls~zjd paldvpv '[InfS lOIOUr

e Ku~o~d~q loj a~g3rd ICraKeur! jo asn '(9561) 'aq1nS 18 '"Ta 'ma- ''~d '8rnq.m~

motor performance of children with mild mental ... mental disabilities after using mental imagery...

Documents