Biology subjects

Poliakoff, E.

Publications and source records attributed to Poliakoff, E..

3 recordsLinked to original sources

bioRxiv2020

Action Imagery and Observation in Neurorehabilitation for Parkinson's Disease (ACTION-PD): development and pilot randomised controlled trial of a user-informed home training intervention to improve everyday functional actions

BackgroundParkinsons disease (PD) causes difficulties with everyday manual activities, but few studies have addressed these therapeutically. Training with action observation (AO) and motor imagery (MI) can significantly improve performance in healthy individuals, particularly when these techniques are applied simultaneously (AO+MI). Both AO and MI have shown promising effects in PD, but previous studies have used these separately. This article describes the development and pilot testing of an intervention combining AO+MI and physical practice to improve functional manual actions in PD. MethodsThe home-based intervention, delivered using a tablet computer app, was iteratively designed by an interdisciplinary team including people with PD, and further developed through focus groups and initial testing. The intervention was then tested in a six-week randomised controlled trial (ISRCTN 11184024) of 10 participants with mild to moderate PD (6 intervention; 4 treatment as usual). Results and ConclusionsUsage and qualitative data provided preliminary evidence of acceptability and usability, indicating that a feasibility RCT is warranted. Exploratory analyses suggested potential improvements in manual actions. The importance of personalisation, choice, and motivation was highlighted, as well as the need to facilitate engagement in motor imagery. The findings also have broader relevance for AO+MI interventions in PD and other populations.

neuroscience↗

bioRxiv2019

Continuous force measurements reveal no inhibitory control deficits in Parkinson’s disease

Suppression of unwanted motor responses can be disrupted by Parkinsons disease. People with Parkinsons (PwP) can show maladaptive reward-driven behaviours in the form of impulse control behaviours, which are associated with use of the dopaminergic treatments used to alleviate the motor symptoms of the disease. However, the effects of Parkinsons itself on impulsive behaviour and control are unclear - empirical studies have yielded mixed findings, and some imaging studies have shown a functional deficit in the absence of a measurable change in behaviour. Here, we investigated the effects of Parkinsons on response activation and control by studying the dynamics of response in standard inhibitory control tasks - the Stop Signal and Simon tasks - using a continuous measure of response force. Our results are largely in favour of the conclusion that response inhibition appears to be intact in PwP, even when using a more sensitive measure of behavioural control relative to traditional button-press measures. Our findings provide some clarity as to the effects of Parkinsons on response inhibition and show continuous response force measurement can provide a sensitive means of detecting erroneous response activity in PwP, which could also be generalised to studying related processes in other populations. Open dataData and analysis can be found on the Open Science Framework (osf.io/kx6h3/) Pre-print templateWiernik, B.M. (2019, October 11). Preprint templates. osf.io/hsv6a/

neuroscience↗

bioRxiv2018

Transcranial alternating current stimulation at 10 Hz modulates response bias in the Somatic Signal Detection Task

BackgroundOngoing, pre-stimulus oscillatory activity in the 8-13 Hz alpha range has been shown to correlate with both true and false reports of peri-threshold somatosensory stimuli. However, to directly test the role of such oscillatory activity in behaviour, it is necessary to manipulate it. Transcranial alternating current stimulation (tACS) offers a method of directly manipulating oscillatory brain activity using a sinusoidal current passed to the scalp.\n\nObjectiveWe tested whether alpha tACS would change somatosensory sensitivity or response bias in a signal detection task in order to test whether alpha oscillations have a causal role in behaviour.\n\nMethodsActive 10 Hz tACS or sham stimulation was applied using electrodes placed bilaterally at positions CP3 and CP4 of the 10-20 electrode placement system. Participants performed the Somatic Signal Detection Task (SSDT), in which they must detect brief somatosensory targets delivered at their detection threshold. These targets are sometimes accompanied by a light flash, which could also occur alone.\n\nResultsActive tACS did not modulate sensitivity to targets but did modulate response criterion. Specifically, we found that active stimulation generally increased touch reporting rates, but particularly increased responding on light trials. Stimulation did not interact with the presence of touch, and thus increased both hits and false alarms.\n\nConclusionstACS stimulation increased reports of touch in a manner consistent with our observational reports, changing response bias, and consistent with a role for alpha activity in somatosensory detection.

neuroscience↗