Adriana Salatino

Imaging the neural mechanisms of TMS neglect-like bias in healthy volunteers with the interleaved TMS/fMRI technique: preliminary evidence

Applying a precisely timed pulse of transcranial magnetic stimulation (TMS) over the right posterior parietal cortex (PPC) can produce temporary visuo-spatial neglect-like effects. Although the TMS is applied over PPC, it is not clear what other brain regions are involved. We applied TMS within a functional magnetic resonance imaging (fMRI) scanner to investigate brain activity during TMS induction of neglect-like bias in three healthy volunteers, while they performed a line bisection judgment task (i.e., the landmark task). Single-pulse TMS at 115% of motor threshold was applied 150 ms after the visual stimulus onset. Participants completed two different TMS/fMRI sessions while performing this task: one session while single-pulse TMS was intermittently and time-locked applied to the right PPC and a control session with TMS positioned over the vertex. Perceptual rightward bias was observed when TMS was delivered over the right PPC. During neglect-like behavior, the fMRI maps showed decreased neural activity within parieto-frontal areas, which are often lesioned or dysfunctional in patients with left neglect. Vertex TMS induced behavioral effects compatible with leftward response bias and increased BOLD signal in the left caudate (a site which has been linked to response bias). These results are discussed in relation to recent findings on neural networks subserving attention in space.

Gait attentional load at different walking speeds

Gait is an attention-demanding task even in healthy young adults. However, scant evidence exists about the attentional load required at various walking speeds. The aim of this study was to investigate motor-cognitive interference while walking at spontaneous, slow and very slow speed on a treadmill while carrying out a backward counting task, in a group (n = 22) of healthy young participants. Cognitive performance was also assessed while sitting. Higher DT cost on the cognitive task was found at spontaneous and very slow walking speed, while at slow walking speed the cognitive task was prioritized with higher DT cost on the motor task. The attentional allocation during DT depends on walking speed with gait prioritization at spontaneous and very slow speed that likely represent more challenging motor conditions.

Awareness of Symptoms Amelioration Following Low-frequency Repetitive Transcranial Magnetic Stimulation in a Patient With Tourette Syndrome and Comorbid Obsessive-compulsive Disorder

Ministry of Education and Research (BMBF, Panic Net Subproject C4; EUROSTARS E! 7675 PONS) and sponsoring for an Investigator Initiated Trial by Astra Zeneca. Dr. Klingberg received public grants not related to this research from the German Ministry of Education and Research (grant no. 01GV0618) and from the German Research Foundation (grant no. KL1179/3-1, KL1179/2-1). B. Wasserka reported no biomedical financial interests or potential conflicts of interest.

Investigating the link between drug-naive first episode psychoses (FEPs), weight gain abnormalities and brain structural damages: Relevance and implications for therapy

ABSTRACT Evidence suggests that obesity and overweight may be associated with severe brain structural abnormalities and poor cognitive and functional outcomes in the general population. Despite these observations and the high prevalence of weight gain abnormalities in patients with psychosis spectrum disorders (PSDs), no studies have investigated the impact that these metabolic disturbances may have on brain structures and development in the earliest stages of PSDs. In the present review we shed light on the association between weight gain and brain structural abnormalities that may affect the course of illness in drug‐naïve FEPs. Given the lack of studies directly investigating this issue, we firstly identified and critically evaluated the literature assessing weight gain abnormalities and gray or white matter (GM, WM) volumes (either globally or in specific regions of interest) in otherwise healthy obese/overweight adolescents and young adults. We then compared the results of this systematic review with those of two recent meta‐analysis investigating GM and WM abnormalities in drug‐naïve FEPs. Weight gain in otherwise healthy subjects was consistently associated with frontal and temporal GM atrophy and with reduced integrity of WM in the corpus callosum. Of relevance, all these brain regions are affected in drug‐naïve FEPs, and their integrity is associated with clinical, cognitive and functional outcomes. The underlying mechanisms that may explain the association between weight gain, adiposity, and brain damage in both healthy subjects and drug‐naïve FEPs are widely discussed. On the basis of this knowledge, we tried: a) to deduce an integrative model for the development of obesity in psychosis spectrum disorders; b) to identify the key vulnerability factors underlying the association between weight gain and psychosis; c) to provide information on new potential targets of intervention. HIGHLIGHTObesity and overweight may increase the severity of brain structural abnormalities associated with FEPs.Obesity and overweight may potentially lead to a more severe course of illness and to worst prognostic outcomes in FEPs.Shared vulnerability factors may explain findings on the high rates of obesity and overweight in drug naive FEPs.In FEPs, early interventions aimed at limiting the development of obesity/overweight may result in better prognostic outcomes.

Rorschach Performance Assessment System (R-PAS) and vulnerability to stress: A preliminary study on electrodermal activity during stress

This study investigated the predictive validity of the ten Rorschach Performance Assessment System (R-PAS) variables from the Stress and Distress domain, by testing whether they predicted increased sympathetic reactivity to a mild, laboratory-induced stress, occurred one week after Rorschach administration. A relatively small student sample (N=52) contributed to this research: During a first meeting (T1) participants were administered the Rorschach task according to R-PAS guidelines; about one week later (T2) their electrodermal activity (EDA) was recorded during exposure to a mild laboratory stress-inducing task. Based on literature indicating that exposure to stress tends to increase physiological vulnerability/reactivity to stressful situations, we anticipated that Stress and Distress R-PAS variables measured at T1 would positively correlate with increased sympathetic reactivity to stress at T2, as indicated by greater EDA changes from baseline to stress and recovery. Results partially confirmed our hypotheses: (a) the mean of and (b) the majority of the Stress and Distress R-PAS variables were significantly correlated, in the expected direction, with medium and medium to large effect sizes.

Comparing intensities and modalities within the sensory attenuation paradigm: Preliminary evidence

Graphical abstract

“As long as that is my hand, that willed action is mine”: Timing of agency triggered by body ownership

We investigated whether agency triggered by body ownership shares similar temporal constraints with agency induced by actual movements. We compared agency over the movements of the own hand, a fake hand and an embodied fake hand when they pressed a button delivering a stimulus to the participants body after 500, 1000 or 2000 ms. In the first two delays, the movement of the embodied fake hand was misattributed to the participants own will and the stimulus intensity was attenuated, as it happened when the own hand delivered the stimulus. With the longest delay, the movement of the embodied fake hand was neither misattributed to the participants will nor the stimulus intensity was attenuated, as it happened when the fake non-embodied hand delivered the stimulus. By showing that illusory and veridical agency arise under similar temporal constraints, we further demonstrated that body ownership per se acts upon agency attribution.

Habitability Issues in Long Duration Space Missions Far from Earth

Living in space today means to stay at an altitude of about 400 km above the Earth surface, on the orbital International Space Station (ISS). In the ‘70s the man reached the Moon but a manned space exploration mission, beyond low Earth orbit and cislunar space, might significantly increase adverse psychophysical effects on human wellbeing. Nowadays, a manned mission to deeper space, such as for example to Mars, is one of the greatest psychological challenge that has never been faced by the humankind. Due to the enormous distance between Earth and Mars, astronauts sent to Mars will be the first human beings who will lose a direct visual link with their Home Planet. Human responses to this and other extreme conditions that might be encountered during long duration missions into deep space are still unknown. In addition, the acute and long term effects of altered gravitational input on the central nervous system and their impact on sensorimotor and cognitive functions need to be clarified to assure maximum performance capabilities during spaceflight and planetary explorations. Our current knowledge on psychological and cognitive effects of orbital spaceflights or analogue environments is not sufficient to reliably assess the specific risks of human mission into outer space. New psychological challenges of mission to Mars will be analyzed with respect to three different areas: individual response and small crew interactions in isolated, confined, and extreme environments (ICE); human adaptation and performance in different gravity environments; concept and methods of psychological countermeasures. The needs of crew members to effectively and safely live and work in space are now referred to missions orbiting around the Earth and have been managed through specific human factors requirements applicable to the ISS. Future manned exploration missions need to reinforce these requirements to design an environment suitable for a safe stay during manned space missions far from Earth. The recommendations of astronauts who have experienced long term stays in space are collected and analyzed to be translated into requirements to be implemented in future space habitats. The analysis of what we have now and what is thought to be relevant to ensure crew wellbeing and performance during long term stays in space is a critical step to assure the success of deep space human missions.

Biased Visuospatial Attention in Cervical Dystonia

OBJECTIVES There is increasing evidence of non-motor, sensory symptoms, mainly involving the spatial domain, in cervical dystonia (CD). These manifestations are likely driven by dysfunctional overactivity of the parietal cortex during the execution of a sensory task. Few studies also suggest the possibility that visuospatial attention might be specifically affected in patients with CD. Therefore, we asked whether non-motor manifestations in CD might also comprise impairment of higher level visuospatial processing. METHODS To this end, we investigated visuospatial attention in 23 CD patients and 12 matched healthy controls (for age, gender, education, and ocular dominance). The patients were identified according to the dystonia pattern type (laterocollis vs. torticollis). Overall, participants were right-handers, and the majority of them was right-eye dominant. Visuospatial attention was assessed using a line bisection task. Participants were asked to bisect horizontal lines, using their right or left hand. RESULTS Participants bisected more to the left of true center when using their left hand to perform the task than when using their right hand. However, overall, torticollis patients produced a significantly greater leftward deviation than controls. CONCLUSIONS These data are consistent with preliminary findings suggesting the presence of biased spatial attention in patients with idiopathic cervical dystonia. The presence of an attentional bias in patients with torticollis seem to indicate that alterations of attentional circuits might be implicated in the pathophysiology of this type of CD. (JINS, 2018, 24, 23-32).

Everything is illuminated: Prismatic adaptation lowers visual detection threshold in normal subjects.

Prismatic adaptation (PA) results from repeated ballistic movements of the dominant arm toward visual targets while wearing prisms shifting the visual field laterally (visuomotor prismatic training [VPT]). Following PA, subjects’ pointing movements are deviated contralaterally to prismatic shift (aftereffect). The question of whether spatial attention is also biased in the same direction remains controversial in the scientific literature. To investigate the effect of PA on spatial attention, we asked healthy participants to perform a visual detection threshold task before and after VPT with left- and right-deviating prisms and visuomotor training without prisms. Our results demonstrate that both left and right VPTs modulate visual detection threshold, significantly ameliorating detection accuracy and response times bilaterally. These data indicate that PA modulates visual attention bilaterally and that detection threshold paradigms are sensitive to its effects in the visual domain. We suggest that the described PA effects are mediated by the joint action of attentional and alerting mechanisms.