The "mirror box" illusion: effect of visual information on bimanual coordination in children with spastic hemiparetic cerebral palsy.
The study examined symmetrical bimanual coordination of children with spastic hemiparetic cerebral palsy (SHCP) and a typically developing (TD) control group under conditions of visual feedback created by placing a glass screen, opaque screen or a mirror ("mirror box") between the arms. The "mirror box" creates a visual illusion, which gives rise to a visual perception of a zero lag, symmetric movement between the two arms. Children with SHCP exhibited a similar mean coordination pattern as the TD control group, but had greater movement variability between the arms. Furthermore, movement variability in children with SHCP was significantly greater in the screen condition compared with the glass and mirror condition, which were similar to each other. The effects of the availability of visual feedback in individuals with hemiparesis are discussed with reference to central and peripheral mechanisms.
Institute for Biomedical Research into Human Movement and Health, Manchester Metropolitan University, Manchester, United Kingdom.
Max G
MG
Feltham
Annick
A
Ledebt
Simon J
SJ
Bennett
Frederik J A
FJ
Deconinck
Martine H G
MH
Verheul
Geert J P
GJ
Savelsbergh
D000293:Adolescent; D000704:Analysis of Variance; D002547:Cerebral Palsy / Q000150:complications / Q000503:physiopathology*; D002648:Child; D056228:Feedback, Sensory / Q000502:physiology*; D005260:Female; D007839:Functional Laterality / Q000502:physiology*; D006801:Humans; D008297:Male; D009068:Movement / Q000502:physiology; D009903:Optical Illusions / Q000502:physiology*; D010291:Paresis / Q000150:complications / Q000503:physiopathology*; D010775:Photic Stimulation; D011597:Psychomotor Performance / Q000502:physiology*; D011930:Reaction Time / Q000502:physiology; D012720:Severity of Illness Index; D014796:Visual Perception / Q000502:physiology