Gross motor skill acquisition in adolescents with Down syndrome
Sarah Meegan, Brian Maraj, Daniel Weeks and Romeo Chua
The purpose of this study was to assess whether verbal-motor performances
deficits exhibited by individuals with Down syndrome limited their ability to acquire gross
motor skills when given visual and verbal instruction together and then transferred to either
a visual or verbal instructional mode to reproduce the movement. Nine individuals with Down
syndrome (6 males, 3 females) performed 3 gross motor skills. Both visual and verbal instructional
guidance was given to the participants over a 4-day period. Twenty-four hours later, the participants
were video recorded as they produced the movements (used as baseline measures). On Day 6, they
were randomly assigned into verbal and visual groups and required to reproduce the skills while
the experimenter provided either visual demonstration or verbal instructions depending on the
group. Based on skill performance scores, participants in the verbal-motor performance group
demonstrated a lower level of proficiency and an increased number of performance errors when
compared to participants in the visual-motor performance group. Moreover, while the visual group
demonstrated an increase in performance levels compared to baseline measures, the opposite effect
was seen for the verbal group.
Meegan S, Maraj BKV, Weeks DJ, Chua R. Gross motor skill acquisition in adolescents with Down syndrome. Down Syndrome Research and Practice. 2006;9(3);75-80.
doi:10.3104/reports.298
Researchers have reported that individuals with Down syndrome initiate and complete movements
more slowly and with greater variability than their peers without disabilities of a similar
chronological age (e.g.,
Johnson and Olley, 1971). In addition to this, persons with Down syndrome
exhibit general information processing difficulties as well as displaying a number of specific
cognitive and motor problems when compared to other individuals with disabilities (Elliott,
Gray and Weeks, 1991). Over the last 20 years, numerous studies have examined the effects of
the unique Down syndrome karyotype on motor behaviour and development. More recently however,
studies involving children and adults with Down syndrome have examined the influences of the
Down syndrome karyotype on cerebral development and specialisation within the population and
its effecting role on motor behaviour (e.g.,
Maraj, Robertson, Welsh, Weeks, Chua, Heath, Roy,
Simon, Weinberg and Elliott, 2002;
Elliott, Weeks and Elliott, 1987;
Weeks, Chua and Elliott,
2000). A primary motivator for these studies has been the idea that atypical patterns of brain
organisation found in persons with Down syndrome (Hartley, 1986;
Pipe, 1988) could be responsible
for some of the information processing difficulties experienced by persons from this population.
For example, while persons with Down syndrome display many general cognitive problems, they
also have difficulty performing tasks involving the perception, organisation and production
of verbal material (Maraj et al., 2003).
Dichotic listening procedures were previously employed in initial neurobehavioural studies to
examine cerebral specialisation for speech perception in Down syndrome (e.g.,
Bowler, Cufflin
and Kiernan, 1985;
Elliott, Weeks and Elliott, 1987;
Elliott, Weeks and Chua, 1994). Dichotic
listening procedures are a non-invasive means of examining cerebral specialisation for speech
perception. In these studies, participants are typically presented with pairs of letters, digits
or words simultaneously to the right and left ears through headphones. Participants can be asked
to either recall all sounds heard or to report the sounds from one ear or the other. In these
situations most right-handed children and adults will report more correct responses for the
right ear than the left ear. The reason for this is that most auditory pathways are contra-lateral
in set-up and as such the advantage of the right ear for the perception has been taken to be
an indication that the left hemisphere is specialised for speech perception. The typical result
when children with Down syndrome engage in dichotic listening procedures is that there is reversed
hemispheric advantage for speech perception. That is, a left-ear right-hemisphere set-up (Chua,
Weeks and Elliot, 1996).
Studies investigating cerebral development (e.g.,
Elliott, Edwards, Weeks, Lindley and Carnahan,
1987;
Parlow, Kinsbourne and Spencer, 1996;
Piccirilli, D'Alessandro, Mazzi, Sciarma, and Testa,
1991) have indicated that although persons with Down syndrome depend on their right hemisphere
for speech perception, their left hemisphere appears to play the executive role in speech production
(Maraj et al., 2002). Of relevance to the motor behaviour domain, left hemisphere specialisation
for speech production is associated with a general lateralised proficiency for specifying the
magnitude and timing of muscular force (Elliott and Chua, 1996). That is, persons with Down
syndrome appear to perceive speech with their right cerebral hemisphere, but depend on their
left cerebral hemisphere for the organisation and control of movement thus, exhibiting atypical
patterns of brain organisation.
In the motor domain, relating to visual and verbal-motor development, persons with Down syndrome
have demonstrated relative proficiency on skills involving the visual demonstration of movement
(Edwards, Elliott and Lee, 1986;
Frith and Frith, 1974;
Le Clair and Elliott, 1995;
Maraj et
al., 2002). Several studies (Elliott, 1990;
Elliott and Weeks, 1990;
Elliott, Weeks and Gray,
1990; Welsh and Elliott, 2001) have shown that adults with Down syndrome exhibit more errors
performing single manual oral gestures to a verbal command (e.g., "place your finger on your
nose") than following the visual demonstration of a task. Elliott, Gray and Weeks (1991) proposed
that the functional isolation of the speech perception (right hemisphere) and movement production
(left hemisphere) systems has led to a breakdown in communication between these systems, adversely
affecting tasks that require verbal-motor behaviour. This proposal had been previously formalised
into a model of cerebral specialisation (Elliott, Weeks, Elliott, 1987).
Subsequent research based on this model has indicated that individuals with Down syndrome experience
difficulties in performing motor tasks based on verbal instruction. The model has been used
in accounting for the information processing difficulties on the basis of verbal instruction.
Further, there is some evidence to suggest that persons with Down syndrome may consolidate visual
information such that positive transfer is seen when they are switched from a visual to verbal
mode of learning. Although much work has been done on simple upper limb movements, real progress
toward influencing broader health and education practices demands that we assess gross motor
skills. Gross motor skills are an important component of many physical activities. Moreover,
the acquisition of these types of motor skills can facilitate many other activities of daily
living. The purpose of this study was to examine gross motor skill acquisition in persons with
Down syndrome based on visual and verbal instructional protocols.
Method
Participants
Participants were nine ambulatory persons with Down syndrome (6 males, 3 females). The participants
were recruited from a daytime summer camp that provided a variety of sports and movement activities
for persons with Down syndrome and was located at the Down Syndrome Research Foundation, British
Columbia, Canada. Ages ranged from 13 to 23 years (M = 19, SD = 3).
Procedure
Over a period of four consecutive days (Phase 1), participants were presented with three different
gross motor skills (hop, step, jump). During this acquisition phase, an instructor taught the
participants each of the three skills utilising both visual and verbal protocols. Phase 2 of
the study was carried out on Day 5 (Baseline), where participants were individually video-recorded
while performing each of the three skills. Each participant was requested to perform the skills
separately and in isolation from other participants. If the participants did not perform the
skill correctly on the first attempt, they were given feedback on their performance followed
by the instructor explaining and demonstrating the skill to them. The participants then were
given another attempt at executing the skill. The movement that was performed following this
procedure was the movement analysed by the researcher. These video recordings served as baseline
data for examination of skill transfer using either a visual or verbal instructional protocol
during Phase 3 of the study.
Phase 3 of the study was carried out on Day 6, where the participants were randomly assigned
to either a visual or verbal group (4 visual, 5 verbal). Participants in the visual group observed
the instructor while they demonstrated the movement skills. Only one demonstration was provided
per skill and participants were required to repeat the movement once only, and immediately following
the instructors demonstration. The verbal group participants were prompted by the instructor
to perform each of the individual skills. The instructor stated the skill (e.g., show me a hop)
and the participant performed the movement. No other information was provided. No feedback was
given to the participants upon the completion of the skills in either the visual or verbal group.
One attempt was allowed for each skill performance. Video recording for Day 6 was carried out
where participants did not view each other executing the skills.
Data analysis
Prior to the video analysis of the skill execution, movement development sequences for the hop,
step, and jump, were prepared by the researcher. The movement sequence for a hop has been partially
validated by Halverson and Williams (1985). The movement sequence for a step has not been validated
but adapted from Roberton and Halverson (1984). The movement sequence for a jump has not been
validated and was adapted from Haywood (1993) and Kirchner and Fishburne (1995).
Each of the skills was broken into 3 separate components: arm, leg and trunk action. Each component
contained ranked developmental steps. The first developmental step was the least mature (in
terms of motor performance) and was ascribed a score of 1, the next developmental step described
a more mature level of skill and received a score of 2. Scoring continued in this fashion until
the most mature step was reached which received the maximum score for the component. Scores
for each component of a movement development sequence were added to ascribe the individual participants
score for the skill. The maximum values for hop, step and jump were 12, 12 and 25, respectively.
A zero score was assigned when a participant did not perform the skill in a particular fashion
e.g., performed a hop instead of a jump, or the participant was unable to perform a component
of a particular skill.
The video data collected for Phases 2 and 3 was then reviewed and each of the 3 movement skills
was analysed and scored. This scoring was based on the developmental steps achieved within each
component for each of the three skills as performed by the participants. Reliability of data
analysis was confirmed by incorporating 3 inter-rater reliability reviews.
Statistical analysis
Statistical analysis was conducted using SPSS for Windows (release 10.0). Descriptive statistics
were computed for all variables (hop, step and jump) on Day 5 and Day 6. An additional descriptive
analysis of the data involved calculating the participants' skill scores on Days 5 and 6 of
the study. This was determined as a percentage of the maximum (mature) value for that skill.
Due to administering multiple comparisons a Bonferroni Adjustment was applied to the alpha level
because multiple t tests result in a greater probability of a Type I error. Alpha was
calculated as p < 0.008. Levene's test for equality of variances was applied to examine the
homogeneity assumption. Subsequently, inferential statistics (independent samples t test)
were carried out.
Figure 1. Means and Standard Deviations of skill scores as a Function of Task and Group for
Phase II (Baseline)
Figure 2. Means and Standard Deviations of skill scores as a Function of Task and Group for
Phase III
Figure 3. Percent change from Phase II to Phase III as a function of Group and Task
Results
The data was analysed using both descriptive and statistical procedures. Levene's test of equality
of variances indicated that no significant difference existed between groups on baseline measurement.
Independent t tests analysis indicated that no significant differences existed between
groups at baseline (Day 5) for the three skills (see Figure 1). After receiving either visual
or verbal instruction on day 6, one significant difference was found between the groups for
the jump skill performance (t (7) = 3.837, p <.006) at level .008 (see
Figure
2). The significant finding at the .008 level was seen as further support that the visual motor
performance group displayed greater jump skill proficiency (M = 14.75, SD = 2.63) than the verbal
motor performance group (M = 2.6, SD = 5.81) Statistical analysis found no significant difference
between visual and verbal-motor performance for a hop and step on the instruction day.
The maximum mature skill scores for the hop, step and jump were 12, 12 and 25, respectively.
Another finding in the current study was the observed differences from the baseline values to
the instruction day values between the visual and verbal groups (based on the mean percentage
of maximum mature skill scores). Results indicated a positive change as reflected by a higher
mean percentage score in the performance of all three skills for the visual group when comparing
Day 5 values to Day 6 values. In contrast, there was an overall decrease in the performance
of all three skills for the participants in the verbal group from Day 5 to Day 6 (see
Figure
3).
Discussion
The purpose of the present study was to investigate whether the verbal-motor performance deficits
exhibited by individuals with Down syndrome (Elliott, 1990;
Elliott and Weeks, 1990;
Elliott,
Weeks and Gray, 1990;
Maraj et al., 2002;
Welsh and Elliott, 2001) limited their ability to
transfer gross motor skills from visual and verbal instruction to either visual or verbal instruction.
Participants were presented with three distinct motor skills and were required to reproduce
the skills under visual or verbal instruction. The inferential results of the current study
are partially consistent with the findings of previous studies based on visual and verbal-motor
performance amongst the Down syndrome population and are particularly pertinent to Elliott et
al. (1987) proposed model of atypical cerebral specialisation (see Chua, Weeks and Elliott (1996)
for a review). The main tenet of this model is that areas responsible for speech perception
are atypically specialised to the right hemisphere in persons with Down syndrome, while the
left hemisphere is involved in the organisation and control of goal-directed movement. The model
posits that persons with Down syndrome will have specific difficulty performing tasks that require
both speech perception and movement organisation. This difficulty is predicted to result because
these tasks are subserved by different cerebral hemispheres. Thus, because inter-hemispheric
communication is required, persons with Down syndrome will exhibit longer information processing
times and/or increased movement errors due to the degradation of information during neural transmission
(Welsh and Elliott, 2001). Specifically, results of the present study provide partial support
for the notion that individuals with Down syndrome have difficulty organising limb movement
based on verbal instruction.
The results for the jump skill showed the most dramatic effect as the verbal group performed
significantly poorer than the visual group. This type of behaviour strategy where "initiate
the movement first, and then figure out the final destination while the movement is being completed"
has been observed in individuals with Down syndrome (Welsh and Elliott, 2001, p.164). As a result
of this, the verbal information to perform the skill (jump) may have still been processed and
decoded throughout the skill execution, thus resulting in more erroneous skill performance.
The unexpected finding of non-significance among verbal-motor performance in two of the presented
motor skills stipulates that verbal-motor performance deficits were not exhibited and thus failed
to limit the participants' skill transfer ability between visual and verbal instruction to verbal
instruction only. This may be attributed to the concept termed 'transfer of learning'. This
concept posits "the gain or loss of a person's proficiency on one task as a result of previous
practice or experience on another task" (Schmidt and Wrisberg, 2000). Pertaining to the results
found in the present study, one may argue that 'positive transfer' of the hop and step skills
occurred as a consequence of 4 consecutive days (acquisition phase) of teaching and practice,
followed by another consecutive day (Day 5) of skill performance under visual and verbal instruction.
It is possible that the participants' prior experience in learning and practicing the skills
had a beneficial effect on the transfer and performance of the hop and step when they were required
to perform them under verbal instruction on Day 6. This is a concept known as generalisation
or 'near transfer'. Near transfer is "a type of transfer of learning that occurs from one task
to another very similar task or situation" (Schmidt and Wrisberg, 2000, p.179).
Contrastingly, participants may have displayed 'negative transfer' of the jump skill where prior
experience was detrimental or non-influential when they were required to reproduce the skill
the following day. It may be that the participants experienced cognitive difficulty under verbal
instruction (as explained in the model of cerebral specialisation) in deciphering the difference
between the skills e.g. a hop and jump, as individuals with Down syndrome exhibit general information
processing difficulties as well as displaying a number of specific cognitive and motor problems
when compared to other individuals with disabilities (Elliott, Gray and Weeks, 1991).
Visual and verbal-motor performances on Day 6 revealed a difference between visual and verbal-motor
performance amongst the participants based on the mean percentage of maximum maturity skill
scores. Specifically, results showed an increase in percentage mean scores for visual-motor
performance for all 3 skills and a contrasting decrease in verbal-motor performance scores for
the equivalent skills. This finding indicates that visual instruction facilitated in greater
skill performance than verbal instruction. This concurs with the findings of previous research
in the visual and verbal-motor domain, stipulating that individuals with Down syndrome tend
to exhibit performance advantages under visual instruction when compared to verbal instruction
(Edwards, Elliott and Lee, 1986;
Frith and Frith, 1974;
Le Clair and Elliott, 1995;
Maraj et
al. 2002). Likewise, individuals with Down syndrome have demonstrated difficulty in performing
tasks involving the perception, organisation and production of verbal material (Maraj et al.,
2002). Once again, the finding of greater performance errors in verbal-motor behaviour may be
attributed to Elliott et al. (1987) model of cerebral specialisation and Elliott, Gray and Weeks
(1991) proposal that individuals with Down syndrome exhibit verbal-motor difficulties as a result
of a dissociation of cerebral systems responsible for speech production and movement organisation.
In conclusion, the present study was an initial investigation into visual and verbal-motor behaviour
amongst persons with Down syndrome utilising gross motor skills. It is fair to deduce that the
verbal-motor performances deficits exhibited by individuals with Down syndrome (Elliott, 1990;
Elliott and Weeks, 1990;
Elliott, Weeks and Gray, 1990;
Maraj et al., 2002;
Welsh and Elliott,
2001) did indeed limit the participants' ability to transfer gross motor skills following visual
and verbal instruction to verbal instruction only. The findings are in agreement with past studies
relating to the visual and verbal-motor behaviour amongst the Down syndrome population. Moreover,
the results ameliorate the proposal that individuals with Down syndrome perform relatively well
on skills involving the visual demonstration of movement when compared to verbal-motor performance
and longer-term retention of gross motor skills.
Acknowledgements
This work was supported by the Social Sciences and Humanities Research Council of Canada.
Correspondence
Dr. Brian Maraj • Perceptual Motor Behaviour Laboratory, Faculty of Physical Education and Recreation,
University of Alberta, Edmonton, AB, Canada T6G 2H9
References
Bowler, D.M., Cufflin, J. & Kiernan, C. (1985). Dichotic listening of verbal and non-verbal
material by Down syndrome children and children of normal intelligence. Cortex, 21,
637-644.
Chua, R., Weeks, D.J. & Elliott, D. (1996). A functional systems approach to understanding
verbal-motor integration in individuals with Down syndrome. Down
Syndrome, Research and
Practice, 4, 25-36. [Open
Access Full Text
]
Edwards, J.M., Elliott, D. & Lee, T.D. (1986). Contextual interference effects during skill
acquisition and transfer in Down syndrome adolescents. Adapted Physical Activity Quarterly,
3, 250-258.
Elliott, D. (1990). Movement control and Down syndrome: A neuropsychological approach. In
Elliott, D., Gray, S., & Weeks, D. J. (1991). In Verbal cueing and motor skill acquisition
for adults with Down syndrome. Adapted Physical Activity Quarterly, 8, 210-220.
Elliott, D. & Chua, R. (1996). Manual asymmetries in goal-directed movement. In D. Elliott
& E.A. Roy (Eds). Manual Asymmetries in Motor Performance (pp. 143-158). Boca Raton:
CRC Press.
Elliott, D., Edwards, J.M., Lindley, S. & Carnahan, H. (1987). Cerebral specialisation in
young adults with Down syndrome. American Journal on Mental Retardation, 91, 480-485.
Elliott, D., Gray, S. & Weeks, D. J. (1991). Verbal cueing and motor skill acquisition for
adults with Down syndrome. Adapted Physical Activity Quarterly, 8, 210-220.
Elliott, D. & Weeks, D.J. (1990). Cerebral specialization and the control of oral and limb
movements for individuals with Down syndrome. Journal of Motor Behaviour, 22, 6-18.
Elliott, D., Weeks, D.J. & Chua, R., (1994). Anomalous cerebral lateralization and Down
syndrome. Brain and Cognition, 26, 191-195.
Elliott, D., Weeks, D.J. & Elliott, C.L., (1987). Cerebral specialisation in individuals
with Down syndrome. American Journal of Mental Retardation, 92, 3, 263-271.
Elliott, D., Weeks, D.J. & Gray, S. (1990). Manual and oral praxis in adults with Down syndrome.
Neuropsychologia, 12, 1307-1315.
Frith, U. & Frith, C.D. (1974). Specific motor disabilities in Down syndrome. Journal
of Child Psychology and Psychiatry, 15, 293-301.
Halverson, L.E. & Williams, K. (1985). Developmental sequences for hopping over distance:
a prelongitudinal screening. Research Quarterly for Exercise and Sport, 56, 37-44.
Hartley, X.Y. (1986). A summary of recent research into the development of children with
Down syndrome. Journal of Mental Deficiency Research, 30, 1-14.
Haywood, K.M. (1993). Life Span Motor Development (2nd ed.). Human Kinetics.
Johnson, J.T., Jr. & Olley, J.G. (1971). Behavioural comparisons of mongoloid and non-mongoloid
retarded persons: A review. American Journal of Mental Deficiency, 75, 546-559.
Kirchner, G. & Fishburne, G. J. (1995). Physical Education for Elementary School Children
(9th ed.). Brown & Benchmark.
Le Clair, D.A. & Elliott, D. (1995). Movement preparation and the costs and benefits associated
with advance information for adults with Down syndrome. Adapted Physical Activity Quarterly,
12, 239-249.
Maraj, B.K.V., Robertson, S.D., Welsh, T.N., Weeks, D.J., Chua, R.C., Heath, M., Roy, E.A.,
Simon, D.A., Weinberg, H.A. & Elliott, D. (2002). Verbal-motor behaviour in persons with
Down syndrome. In M. Cuskelly, A. Jobling & S. Buckley (Eds) Down Syndrome Across the
Lifespan. Pp. 175-193. London, England: Whurr Publishers Ltd.
Maraj, B.K.V., Li, L., Hillman, R., Jeansonne, J. & Robertson, S.D. (2003). Verbal and visual
instruction in motor skill acquisition for persons with and without Down syndrome. Adapted
Physical Activity Quarterly, 20, 57-69.
Parlow, S.E., Kinsbourne, M. & Spencer, J. (1996). Cerebral laterality in adults with severe
mental retardation. Developmental Neuropsychology, 12, 299-312.
Piccirilli, M., D'Alessandro, P., Mazzi, P., Sciarma, T. & Testa, A. (1991). Cerebral organization
for language in Down's syndrome patients. Cortex, 27, 41-47.
Pipe, M.E. (1988). Atypical laterality and retardation. Psychological Bulletin, 104,
343-349.
Roberton, M.A. & Halverson, L.E. (1984). Developing children - their changing movement.
Philadelphia: Lea & Febiger. In Haywood, D.J. (1993). Life Span Motor Development (2nd
ed.). Human Kinetics.
Schmidt, R. A. & Wrisberg, C. A. (2000). Motor Learning and Performance. A Problem-Based
Learning Approach (2nd ed.). Human Kinetics.
Weeks, D.J., Chua, R. & Elliott, D. (Eds.). (2000). Perceptual Motor Behaviour in Down
Syndrome. Champaign, IL: Human Kinetics.
Welsh, T.N. & Elliott, D. (2000). The preparation and control of goal-directed limb movement
in persons with Down syndrome. In Weeks, D. J., Chua, R. & Elliott, D. (2000). Perceptual-Motor
Behaviour in Down Syndrome. Human Kinetics.
Welsh, T.N. & Elliott, D. (2001). The processing speed of visual and verbal movement information
by adults with and without Down syndrome. Adapted Physical Activity Quarterly, 18,
156-167.