The developmental relationship between motor skills and large-scale spatial knowledge
Attention Deficit Hyperactivity Disorder (ADHD) is the most common neurodevelopmental disorder in childhood. Where studies have investigated motor abilities (balance, ball skills, hand and finger movements), difficulties are reported for this group. Given the importance of motor abilities in everyday life (in social interaction, to produce language, for handwriting and for activities of daily living such as eating), knowledge is surprisingly limited in this area. We explored the motor system in ADHD in detail.
A developmental consequence of poor motor ability is a poor understanding of large scale space, i.e. navigation, crucial for getting around the environment. We also measured navigation (using virtual reality). We predict that navigation skills will be poor in ADHD. This study was the first to investigate navigation and how it relates to motor deficits in ADHD. It is crucial to establish the developmental links across different types of behaviour, because it is possible that difficulties in one area (navigation) stem from difficulties in another area (motor) that develops earlier in life. Knowledge of the developmental consequences of impaired motor abilities in ADHD enables one to decide when and how to intervene in order to help people with ADHD to achieve their optimal potential, not just in the motor domain, but in other areas, navigation being just one example. ADHD performance was compared to performance in the typical population. We also compared ADHD to Williams syndrome (WS), a genetically defined neurodevelopmental disorder in which both attention and motor deficits are reported. This was to determine which difficulties and developmental patterns are specific to ADHD.
- Aislinn Bowler
- Leighanne Mayall
- Annette Karmiloff-Smith
- Elisabeth Hill
- Hana D'Souza
Summary of our findings
The ADHD group was split into two groups based on their motor scores. There was a high motor group, ADHD-H group who had average or above average motor skills (based on the Bruininks-Oseretsky Test of Motor Proficiency Second Edition Short Form [BOT2-SF]; Bruininks, 2005) and a Low motor group, ADHD-L who had below or well-below average motor skills (based on the BOT2-SF). Consistent with the literature, 17 / 39 of participants with ADHD displayed impaired motor ability. Profile analysis of the eight BOT2-SF subtests demonstrated that the impairment is not uniform. Both ADHD subgroups displayed atypical motor profiles across the eight BOT2 subtests, relative to typically developing (TD) (N=72) control children. Interestingly, motor milestone achievement was not delayed in either the ADHD-L or ADHD-H group. Few relationships were observed between ADHD core characteristics and motor competence. We conclude that the motor deficit observed in a large proportion of children with ADHD is not inherent to ADHD. The typical achievement of motor milestones in ADHD, and the parallel profile of motor abilities of the ADHD-L and ADHD-H groups, suggests that the motor deficit observed in some children with ADHD is a result of subtle impairments in infancy, which impact motor development. Thus, we propose that whilst a motor impairment is not related to ADHD core characteristics, it is a developmental consequence of ADHD (rather than a completely unrelated co-occurring deficit) which impacts some but not all children with ADHD. The protective factors which attenuate this developmental cascade in children with ADHD and no motor impairment require further research as this has important implications for intervention. This will be the focus of our next study, which will run during 2019/20.
The spatial performance in both ADHD groups, measured through a novel virtual reality maze game, did not differ from that of the TD control group. Results demonstrated a relationship between fine motor ability and spatial navigation in the TD group, which could reflect the developmental impact of the ability to manually manipulate objects, on spatial knowledge. In contrast, no relationships between the motor and spatial domains were observed for the ADHD or WS groups. Indeed, whilst there was evidence of motor impairment in both groups, only the WS group demonstrated an impairment in large-scale spatial navigation. The motor-spatial relationship in the TD, but not the ADHD and WS groups, suggests that spatial cognition can develop via a developmental pathway which bypasses input from the motor domain. Thus, cross-syndrome comparison with the ADHD group demonstrates that poor motor ability does not always predict poor spatial cognition.
Mayall, L.A., D’Souza, H., Hill, E.L., Karmiloff-Smith, A., Tolmie, A., Farran, E.K. (2020). Motor Abilities and the Motor Profile in Individuals with Williams Syndrome. Advances in Neurodevelopmental Disorders. https://doi.org/10.1007/s41252-020-00173-8
Farran, E.K., Bowler, A., D’Souza, H., Mayall, L., Karmiloff-Smith, A., Sumner, E., Brady, D., Hill, E.L (2020). Is the Motor Impairment in Attention Deficit Hyperactivity Disorder (ADHD) a Co-Occurring Deficit or a Phenotypic Characteristic? Advances in Neurodevelopmental Disorders. https://doi.org/10.1007/s41252-020-00159-6
Farran, E.K., Bowler, A., Karmiloff-Smith, A., D’Souza, H., Mayall, L., Hill, E.L. (2019). Cross-domain associations between motor ability, independent exploration and large-scale spatial navigation; Attention Deficit Hyperactivity Disorder, Williams syndrome and typical development. Frontiers in Human Neuroscience. https://doi.org/10.3389/fnhum.2019.00225
Research groups and centres
Our research is supported by research groups and centres of excellence.