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Dual-task and electrophysiological markers of executive cognitive processing in older adult gait and fall-risk.

Walshe EA, Patterson MR, Commins S, Roche RA - Front Hum Neurosci (2015)

Bottom Line: Experiment 1 employed a dual-task (DT) paradigm in young and older adults, to assess the relative effects of higher-level executive function tasks (n-Back, Serial Subtraction and visuo-spatial Clock task) in comparison to non-executive distracter tasks (motor response task and alphabet recitation) on gait.Significantly greater DT costs were observed for the executive tasks in the older adult group.No significant differences in cognitive performances were found between fallers and non-fallers.

View Article: PubMed Central - PubMed

Affiliation: Department of Psychology, Maynooth University Maynooth, Kildare, Ireland.

ABSTRACT
The role of cognition is becoming increasingly central to our understanding of the complexity of walking gait. In particular, higher-level executive functions are suggested to play a key role in gait and fall-risk, but the specific underlying neurocognitive processes remain unclear. Here, we report two experiments which investigated the cognitive and neural processes underlying older adult gait and falls. Experiment 1 employed a dual-task (DT) paradigm in young and older adults, to assess the relative effects of higher-level executive function tasks (n-Back, Serial Subtraction and visuo-spatial Clock task) in comparison to non-executive distracter tasks (motor response task and alphabet recitation) on gait. All DTs elicited changes in gait for both young and older adults, relative to baseline walking. Significantly greater DT costs were observed for the executive tasks in the older adult group. Experiment 2 compared normal walking gait, seated cognitive performances and concurrent event-related brain potentials (ERPs) in healthy young and older adults, to older adult fallers. No significant differences in cognitive performances were found between fallers and non-fallers. However, an initial late-positivity, considered a potential early P3a, was evident on the Stroop task for older non-fallers, which was notably absent in older fallers. We argue that executive control functions play a prominent role in walking and gait, but the use of neurocognitive processes as a predictor of fall-risk needs further investigation.

No MeSH data available.


Related in: MedlinePlus

Stroop task P3a event-related potentials (ERPs) recorded at midline and occipital electrodes Pz (top) and Oz (bottom) for young (green), older non-faller (blue) and older faller (red) groups for congruent and incongruent trials. Scalp topographies for maximal P3a amplitude on congruent trials (at 229 ms) and incongruent trials (at 234 ms) are shown for each group.
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Figure 2: Stroop task P3a event-related potentials (ERPs) recorded at midline and occipital electrodes Pz (top) and Oz (bottom) for young (green), older non-faller (blue) and older faller (red) groups for congruent and incongruent trials. Scalp topographies for maximal P3a amplitude on congruent trials (at 229 ms) and incongruent trials (at 234 ms) are shown for each group.

Mentions: A repeated measures ANOVA revealed a main effect of group for this early P3 peak; F(2,31) = 4.88, p = 0.014, = 0.24. Planned comparisons between the ONF and OF groups revealed a significantly greater peak amplitude for the ONF group on congruent trials at both Pz (OF: M = 0.23, SD = 0.34; ONF: M = 1.39, SD = 0.92) and Oz (OF: M = 0.36, SD = 1.33; ONF: M = 3.41, SD = 2.69). Peak amplitude was also greater for ONF (M = 2.71, SD = 2.68) than OF (M = 0.18, SD = 1.29) on incongruent trials at Oz. Figure 2 illustrates this suggested early P3 (P3a) waveform at Pz and Oz, with Oz scalp topographies at the ONF peak amplitude (congruent: 229 ms; incongruent: 234 ms). There was no main effect for group on P3a latency; F(2,32) = 0.42, p = 0.66 (corroborating previous findings: West and Alain, 2000).


Dual-task and electrophysiological markers of executive cognitive processing in older adult gait and fall-risk.

Walshe EA, Patterson MR, Commins S, Roche RA - Front Hum Neurosci (2015)

Stroop task P3a event-related potentials (ERPs) recorded at midline and occipital electrodes Pz (top) and Oz (bottom) for young (green), older non-faller (blue) and older faller (red) groups for congruent and incongruent trials. Scalp topographies for maximal P3a amplitude on congruent trials (at 229 ms) and incongruent trials (at 234 ms) are shown for each group.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4400911&req=5

Figure 2: Stroop task P3a event-related potentials (ERPs) recorded at midline and occipital electrodes Pz (top) and Oz (bottom) for young (green), older non-faller (blue) and older faller (red) groups for congruent and incongruent trials. Scalp topographies for maximal P3a amplitude on congruent trials (at 229 ms) and incongruent trials (at 234 ms) are shown for each group.
Mentions: A repeated measures ANOVA revealed a main effect of group for this early P3 peak; F(2,31) = 4.88, p = 0.014, = 0.24. Planned comparisons between the ONF and OF groups revealed a significantly greater peak amplitude for the ONF group on congruent trials at both Pz (OF: M = 0.23, SD = 0.34; ONF: M = 1.39, SD = 0.92) and Oz (OF: M = 0.36, SD = 1.33; ONF: M = 3.41, SD = 2.69). Peak amplitude was also greater for ONF (M = 2.71, SD = 2.68) than OF (M = 0.18, SD = 1.29) on incongruent trials at Oz. Figure 2 illustrates this suggested early P3 (P3a) waveform at Pz and Oz, with Oz scalp topographies at the ONF peak amplitude (congruent: 229 ms; incongruent: 234 ms). There was no main effect for group on P3a latency; F(2,32) = 0.42, p = 0.66 (corroborating previous findings: West and Alain, 2000).

Bottom Line: Experiment 1 employed a dual-task (DT) paradigm in young and older adults, to assess the relative effects of higher-level executive function tasks (n-Back, Serial Subtraction and visuo-spatial Clock task) in comparison to non-executive distracter tasks (motor response task and alphabet recitation) on gait.Significantly greater DT costs were observed for the executive tasks in the older adult group.No significant differences in cognitive performances were found between fallers and non-fallers.

View Article: PubMed Central - PubMed

Affiliation: Department of Psychology, Maynooth University Maynooth, Kildare, Ireland.

ABSTRACT
The role of cognition is becoming increasingly central to our understanding of the complexity of walking gait. In particular, higher-level executive functions are suggested to play a key role in gait and fall-risk, but the specific underlying neurocognitive processes remain unclear. Here, we report two experiments which investigated the cognitive and neural processes underlying older adult gait and falls. Experiment 1 employed a dual-task (DT) paradigm in young and older adults, to assess the relative effects of higher-level executive function tasks (n-Back, Serial Subtraction and visuo-spatial Clock task) in comparison to non-executive distracter tasks (motor response task and alphabet recitation) on gait. All DTs elicited changes in gait for both young and older adults, relative to baseline walking. Significantly greater DT costs were observed for the executive tasks in the older adult group. Experiment 2 compared normal walking gait, seated cognitive performances and concurrent event-related brain potentials (ERPs) in healthy young and older adults, to older adult fallers. No significant differences in cognitive performances were found between fallers and non-fallers. However, an initial late-positivity, considered a potential early P3a, was evident on the Stroop task for older non-fallers, which was notably absent in older fallers. We argue that executive control functions play a prominent role in walking and gait, but the use of neurocognitive processes as a predictor of fall-risk needs further investigation.

No MeSH data available.


Related in: MedlinePlus