title: The influence of attention and age on the occurrence of mirror movements.
abstract: This study utilised a finger force task to investigate the influence of attention and age on the occurrence of motor overflow in the form of mirror movements in neurologically intact adults. Forty right-handed participants were recruited from three age groups: 20-30 years, 40-50 years, and 60-70 years. Participants were required to maintain a target force using both their index and middle fingers, representing 50% of their maximum strength capacity for that hand. Attention was directed to a hand by activating a bone conduction vibrator attached to the small finger of that hand. Based on Cabeza's (2002) model of hemispheric asymmetry reduction in older adults, it was hypothesised that mirror movements would increase with age. Furthermore, it was expected that when the attentional demands of the task were increased, motor overflow occurrence would be exacerbated for the older adult group. The results obtained provide support for the model, and qualified support for the hypothesis that increasing the attentional demands of a task results in greater motor overflow. It is proposed that the association between mirror movements and age observed in this study may result from an age-related increase in bihemispheric activation that occurs in older adults, who, unlike younger adults, benefit from bihemispheric processing for task performance.
authors.affiliation: School of Psychology, Deakin University, Geelong, Victoria, Australia.
authors.forename: Yasmin
authors.initials: Y
authors.lastname: Baliz
authors.forename: Christine
authors.initials: C
authors.lastname: Armatas
authors.forename: Maree
authors.initials: M
authors.lastname: Farrow
authors.forename: Kate E
authors.initials: KE
authors.lastname: Hoy
authors.forename: Paul B
authors.initials: PB
authors.lastname: Fitzgerald
authors.forename: John L
authors.initials: JL
authors.lastname: Bradshaw
authors.forename: Nellie
authors.initials: N
authors.lastname: Georgiou-Karistianis
mesh_terms: D000328:Adult; D000368:Aged; D000375:Aging / Q000523:psychology*; D001288:Attention / Q000502:physiology*; D003627:Data Interpretation, Statistical; D005260:Female; D005385:Fingers / Q000294:innervation / Q000502:physiology; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009068:Movement / Q000502:physiology*; D009483:Neuropsychological Tests; D011795:Surveys and Questionnaires