Parkinson’s from inside out: emerging and unexpected benefits of a long-term partnership

This article is a personal reflection on a long-standing patient and public involvement (PPI) partnership between a person with Parkinson’s and a cognitive neuroscience researcher. They describe how the partnership arose, was established and evolved to produce unexpected benefits to the research and more broadly. Initially, working together helped to communicate the purpose of the research to a lay audience and to make lab-based testing sessions for people with Parkinson’s as comfortable as possible. They then worked together on the steering group for a research project about Parkinson’s and imitation, which led to co-designing interventions using imitation and imagination of movements to improve movements, including a dance class. Further benefits were realised through co-teaching undergraduate students about Parkinson’s, establishing a broader culture of PPI within the research lab and sharing their expertise of PPI more broadly. They consider key ingredients for successful collaboration, including shared curiosity, open-mindedness and trust, as well as the importance of informal discussion and space. Challenges are also considered, including authorship of research articles and anonymity. Their account demonstrates the value of the collaboration to research itself, but also the broader (often unexpected) benefits that can emerge when a collaboration has space and time to flourish

Evaluation by simulation of interpolation and acceleration algorithms for Stepper Motors

Stepper motors are used to control CNC machines for many applications. As well as following the required path precisely, it is also important that the motion be smooth and that the surface speed be controllable. Improved interpolation algorithms for individual straight lines and circular arcs have been developed using distance as a parameter [Chow et al, 2002], [Chow, 2003]. The algorithms control the motor by means of pulses and the generation of the pulse timings is based on the geometry of the shape. For high speeds it is necessary to allow smooth acceleration at the beginning and similar smooth deceleration at the end. Thus, appropriate acceleration and deceleration algorithms have been developed for use with the new interpolation algorithms. This paper describes how simulation has been used to evaluate the new algorithms and compare them with previous algorithms. The algorithms are described for the 2D case but the principle can be extended to 3D

Vibrational branching ratios in photoionization of CO and N2

We report results of experimental and theoretical studies of the vibrational branching ratios for CO 4sigma(-1) photoionization from 20 to 185 eV. Comparison with results for the 2sigma(u)(-1) channel of the isoelectronic N-2 molecule shows the branching ratios for these two systems to be qualitatively different due to the underlying scattering dynamics: CO has a shape resonance at low energy but lacks a Cooper minimum at higher energies whereas the situation is reversed for N-2

The case for a wet, warm climate on early Mars

Arguments are presented in support of the idea that Mars possessed a dense CO2 atmosphere and a wet, warm climate early in its history. The plausibility of a CO2 greenhouse is tested by formulating a simple model of the CO2 geochemical cycle on early Mars. By scaling the rate of silicate weathering on Earth, researchers estimated a weathering time constant of the order of several times 10 to the 7th power years for early Mars. Thus, a dense atmosphere could have existed for a geologically significant time period (approx. 10 to the 9th power years) only if atmospheric CO2 was being continuously resupplied. The most likely mechanism by which this could have been accomplished is the thermal decomposition of carbonate rocks induced directly or indirectly by intense, global scale volcanism

Molecular photoionization as a probe of vibrational–rotational–electronic correlations

We determine the rotationally state‐resolved 2σ_u^(−1) photoionization of N_2 into alternative vibrational channels as a function of energy over a 200 eV range. Experiment and theory reveal that Cooper minima highlight the coupling between electronic, vibrational, and rotational degrees of freedom over this very wide range

Interoceptive and exteroceptive attention have opposite effects on subsequent somatosensory perceptual decision making

Evidence suggests that interoceptive and exteroceptive attention might have different perceptual effects. However, the effects of these different types of body-focused attention have never been directly compared. The current research investigated how interoceptive and exteroceptive attention affect subsequent performance on the somatic signal detection task (SSDT). In Experiment 1, 37 participants completed the SSDT under usual testing conditions and after performing an interoceptive heartbeat perception task. This task led to a more liberal response criterion, leading to increased touch reports in the presence and absence of a target vibration. This finding is consistent with suggestions that attending internally contributes to physical symptom reporting in patients with medically unexplained symptoms (MUS). In Experiment 2, 40 participants completed the SSDT before and after an exteroceptive grating orientation task. This task led to a more stringent response criterion, leading to decreased touch reports in the presence and absence of the target, possibly via a reduction in sensory noise. This work demonstrates that internal and external body-focused attention can have opposite effects on subsequent somatic perceptual decision making and suggests that attentional training could be useful for patients reporting MUS. </jats:p

I feel bad and look worse than you: Social comparisons moderate the effect of mood on face health judgement

Mood can bias the judgements people make about themselves and how people compare themselves to others. However, it is not yet clear whether mood also affects appearance-based self-evaluations and social comparisons. Given the importance of perceived health status for well-being, we investigated the effect of mood on self-image and social comparisons of healthiness during two versions of a face health judgement task. Thirty participants judged how they felt compared to healthy and unhealthy looking versions of their own (self version) and a stranger’s face (stranger version), after a positive, negative and neutral mood induction. The effect of mood was dependent on self/stranger task order. Although mood did not affect face health judgement for participants who initially judged themselves against their own face, it did affect face health judgement for participants who initially judged themselves in comparison to a stranger’s face. After the positive and negative mood inductions, these participants judged themselves as equivalent to healthier/unhealthier looking versions of their own and stranger’s faces, respectively. Thus, social comparisons of facial healthiness could provide a perceptual measure of state well-being

Global Franck-Condon breakdown resulting from Cooper minima

Using N2 2σu-1 photoionization as an example, we present the first measurements and calculations of photoion vibrational distributions for an extended energy range ( 5≤Ek≤230 eV). The results show a striking breakdown of the Franck-Condon approximation over a 100 eV range. We show that this coupling between vibrational and electronic motion arises from a dependence of Cooper minima on molecular bond length. Based on this mechanism, the effect is expected to be common for molecular systems

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

Ongoing, 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. We 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. Active 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. Active 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. ACS 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