Age-Related Interference between the Selection of Input-Output Modality Mappings and Postural Control—a Pilot Study

Abstract

Age-related decline in executive functions and postural control due to degenerative processes in the central nervous system have been related to increased fall-risk in old age. Many studies have shown cognitive-postural dual-task interference in old adults, but research on the role of specific executive functions in this context has just begun. In this study, we addressed the question whether postural control is impaired depending on the coordination of concurrent response-selection processes related to the compatibility of input and output modality mappings as compared to impairments related to working-memory load in the comparison of cognitive dual and single tasks. Specifically, we measured total center of pressure (CoP) displacements in healthy female participants aged 19–30 and 66–84 years while they performed different versions of a spatial one-back working memory task during semi-tandem stance on an unstable surface (i.e., balance pad) while standing on a force plate. The specific working-memory tasks comprised: (i) modality compatible single tasks (i.e., visual-manual or auditory-vocal tasks), (ii) modality compatible dual tasks (i.e., visual-manual and auditory-vocal tasks), (iii) modality incompatible single tasks (i.e., visual-vocal or auditory-manual tasks), and (iv) modality incompatible dual tasks (i.e., visual-vocal and auditory-manual tasks). In addition, participants performed the same tasks while sitting. As expected from previous research, old adults showed generally impaired performance under high working-memory load (i.e., dual vs. single one-back task). In addition, modality compatibility affected one-back performance in dual-task but not in single-task conditions with strikingly pronounced impairments in old adults. Notably, the modality incompatible dual task also resulted in a selective increase in total CoP displacements compared to the modality compatible dual task in the old but not in the young participants. These results suggest that in addition to effects of working-memory load, processes related to simultaneously overcoming special linkages between input- and output modalities interfere with postural control in old but not in young female adults. Our preliminary data provide further evidence for the involvement of cognitive control processes in postural tasks.

Behavioral and Neural Correlates of Cognitive-Motor Interference during Multitasking in Young and Old Adults

“…The finding that there was no difference in total CoP displacements under CP and CCP conditions in old adults seems congruent with the idea of dynamic adaptations depending on the task load. Note that in our previous study, relative costs in postural sway (not absolute displacement) of old adults was enhanced in triple- (CCP) compared to dual-task (CP) conditions, but only under certain additional task requirements such as the type of input-output modality mappings, which were not part of the present study [17]. This suggests, that various factors (e.g., age and task type) might affect behavioral adaptations to task requirements in cognitive-postural multitasking.…”

“…Furthermore, age-related decrements during the concurrent performance of cognitive and motor tasks are disproportionately greater than the additive age-related costs of performing the two tasks independently (dual-task costs) [14, 15]. In general, old adults show greater cognitive-motor interference than younger adults [16, 17]. However, with increasing postural demands, elderly seem to prioritize their attentional resources to control posture and to neglect cognitive performance [18, 19].…”

Contribution of the Lateral Prefrontal Cortex to Cognitive-Postural Multitasking

“…In each session, three runs were conducted in standing upright position and three while sitting upright, performed in an alternating mode. The sessions differed in the specific stimulus-response mappings to be performed, i.e., in one session only visual-manual and auditory-vocal tasks were realized, in the other session only visual-vocal and auditory manual tasks (see Stelzel et al (2017) for more details).…”

Cognitive-Postural Multitasking Training in Older Adults – Effects of Input-Output Modality Mappings on Cognitive Performance and Postural Control

“…The cognitive demand to disentangle the overlap between sensory input modality, anticipated response effects and actual responses between two concurrently relevant task sets ( Greenwald & Shulman, 1973 ; Hommel, 1998 ; Prinz, 1990 ) might be one central component of the involved control demands ( Schacherer & Hazeltine, 2020 ). Our findings ( Stelzel et al, 2017 ) indicate (i) that modality mappings also affect performance in continuous working-memory tasks, more similar in nature to maintaining postural stability than single-trial response-selection tasks and (ii) that task load and modality compatibility mappings both interfere with postural control in old age. Interference was highest, when cognitive task load was high (dual one-back task) and control demands were high (modality incompatible dual task).…”

“…Here, we focused on the role of specific input-output modality pairings that have been shown to affect multitasking performance in the cognitive domain ( Hazeltine et al, 2006 ; Stelzel et al, 2006 ; Stephan & Koch, 2010 ). Modality incompatible stimulus-response mappings interfere with each other to a greater extent than modality compatible mappings, and – in old adults – they also seem to interfere more with postural demands ( Stelzel et al, 2017 ). Whether an adaptive cognitive-postural training intervention involving these demanding stimulus-response mappings leads to domain-specific effects is unknown but functionally and clinically highly relevant.…”