Cognitive-motor interference during standing stance across different postural and cognitive tasks in individuals with Down syndrome

Background: Individuals with Down syndrome (DS) presented both cognitive and motor impair-ments that could influence each other. Therefore, exploring cognitive-motor interference during standing stance is relevant in this population.Aims: This study explored the dual task (DT) effects on postural balance during diverse cognitive tasks and sensory manipulations in individuals with DS, compared to those with typical devel-opment (TD).Methods and procedures: Fifteen adolescents with DS (age = 14.26 & PLUSMN; 1.27 years; height = 1.50 & PLUSMN; 0.02; weight = 46.46 & PLUSMN; 4.03 kg; BMI =20.54 & PLUSMN; 1.51 kg/m2) and thirteen with TD (age = 14.07 & PLUSMN; 1.11 years; height = 1.50 & PLUSMN; 0.05; weight = 44.92 & PLUSMN; 4.15 kg; BMI =19.77 & PLUSMN; 0.94 kg/m2) participated in this study. Postural and cognitive performances for the selective span task (SST) and the verbal fluency (VF) were recorded during single task (ST) and DT conditions. Postural conditions were: firm eyes open (firm-EO), firm eyes closed (firm-EC) and foam-EO. Motor and cognitive DT costs (DTC) were calculated and analyzed across these different cognitive and postural conditions.Outcomes and results: In the DS group, postural performance was significantly (p < 0.001) altered during all DT conditions, compared to the ST situation. Moreover, the motor DTC was signifi-cantly (p < 0.001) higher while performing the VF task than the SST. However, in the control group, postural performance was significantly (p < 0.001) impaired only while performing the VF test in the DT-Firm EO condition. For both groups, cognitive performances were significantly (p < 0.05) altered in all DT conditions compared to the ST one.Conclusion: Adolescents with DS are more prone to DT effects on postural balance than those with TD.