Walking while talking – a special kind of walking

Abstract

Abstract Background: Dual tasking is challenging with increasing age, particularly when one of the components is walking. The mechanisms of reduced dual task abilities caused by age or neurodegenerative diseases have not been sufficiently understood yet. Functional brain imaging would be a useful diagnostic procedure, but functional magnetic resonance imaging is not feasible for whole body movements. Functional near-infrared spectroscopy (fNIRS) may be a suitable technique to measure body movement effects on fronto-temporo-parietal cortical activation in single and dual task paradigms. Method: 12 young healthy adults walked on a treadmill at different speeds (3 and 5 km/h; single task (ST) paradigms) and, additionally, during a simultaneous performing of a verbal fluency task (while walking at 3km/h; dual task (DT) paradigm). Brain activation was measured using fNIRS at the scalp over the frontal, temporal and parietal cortex of both hemispheres with two large 4 x 4 probe-sets with 24 channels each during single and dual tasks. Findings: With increasing challenge, Broca’s area showed an increased activation during the more advanced conditions (ST-5km/h > ST-3km/h, DT > ST-3km/h, DT > ST-5km/h), while the corresponding area on the right hemisphere was also activated. Discussion: DT paradigms combining walking and a cognitive task elicit wide-spread cortical activation patterns across fronto-temporo-parietal areas. fNIRS is a suitable method for functional measurements of walking and dual tasking. Due to the high ecological validity and the good acceptance of fNIRS also for aged participants the next steps are dual task measurements of elderly and subjects with neurodegenerative diseases.