The “Mirror Box” Illusion: Effect of Visual Information on Bimanual Coordination in Children with Spastic Hemiparetic Cerebral Palsy

Abstract

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.

Mirror therapy in children with hemiparesis: a randomized observer‐blinded trial

“…There is only scarce evidence of a specific effect of mirror visual feedback in children with hemiparesis. Four studies investigating the effect of mirror visual feedback in these children using movement analysis demonstrated improvements in active joint position sense, modulation of proximal arm muscle activity, and a lack of effect on movement variability . None of these studies were geared towards exploring the potential efficacy of mirror therapy as a training programme.…”

Reflections on Mirror Therapy

“…84 To date the majority of evidence stems from studies in healthy adult individuals and the few studies that have examined a patient population only considered people who survived a stroke. It remains unclear to what extent these hypotheses may be valid for other clinical conditions for which MVF has been suggested an adjunct to conventional therapy (eg, SHCP 22,[85][86][87] and CRPS [14][15][16][17][18] ). The finding that MVF may have an impact on multiple functional networks may mean it can serve as a versatile tool to promote motor recovery, of which the actual mechanism is dependent on the specific condition or damage.…”

Mirror Therapy: A Review of Evidences

“…In addition, the mirror lead to shorter relative durations of eccentric and concentric activity in the elbow muscles of the more impaired arm, whereas no effects of visual feedback were found in a matched control group. These results suggest that replacing veridical visual information of the more impaired arm with a mirror reflection of the less impaired arm improves the motor control of children with SHCP during inter limb coupling [6].…”