Article

Gait is influenced by higher order cognitive and cortical control
mechanisms. Functional near infrared spectroscopy (fNIRS) has been used to
examine frontal activation during walking in healthy older adults, reporting
increased oxygenated hemoglobin (HbO2) levels during dual task walking (DT),
compared with usual walking. OBJECTIVE: To investigate the role of the frontal
lobe during DT and obstacle negotiation, in healthy older adults and patients
with Parkinson's disease (PD). METHODS: Thirty-eight healthy older adults (mean
age 70.4 +/- 0.9 years) and 68 patients with PD (mean age 71.7 +/- 1.1 years,)
performed 3 walking tasks: (a) usual walking, (b) DT walking, and (c) obstacles
negotiation, with fNIRS and accelerometers. Linear-mix models were used to detect
changes between groups and within tasks. RESULTS: Patients with PD had higher
activation during usual walking (P < .030). During DT, HbO2 increased only in
healthy older adults (P < .001). During obstacle negotiation, HbO2 increased in
patients with PD (P = .001) and tended to increase in healthy older adults (P =
.053). Higher DT and obstacle cost (P < .003) and worse cognitive performance
were observed in patients with PD (P = .001). CONCLUSIONS: A different pattern of
frontal activation during walking was observed between groups. The higher
activation during usual walking in patients with PD suggests that the prefrontal
cortex plays an important role already during simple walking. However, higher
activation relative to baseline during obstacle negotiation and not during DT in
the patients with PD demonstrates that prefrontal activation depends on the
nature of the task. These findings may have important implications for
rehabilitation of gait in patients with PD.
CI - (c) The Author(s) 2016.

Langue : ANGLAIS