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Human manual actions are selected based on object properties but also goal-directed and habitual constraints. Although the goal-directed constraints have extensively been studied, little is known about habitual constraints. In this experiment, we investigated the neurophysiological mechanisms of grasping habits during motor planning. Twenty-two right-handed volunteers were asked to grasp a handle (habitually or non-habitually) and then rotated the handle (i.e., the end with a pointing marker) to a target position. In the habitual trials, participants grasped the handle with their thumb toward the pointing marker. In the non-habitual trials, participants grasped the handle with their thumbs away from the pointing marker. Movement timing parameters (reaction, reach, and rotation time) and movement-related cortical potentials (MRCPs) were recorded. Behaviorally, reaction, reach, and rotation times were shorter for habitual than for non-habitual grasp-ing (all F(1,21)s > 7.3; all ps < .05). Neurophysiologically, in the time window 500 ms before movement onset, posterior MRCPs were more negative-going for the non-habitual than for the habitual grasping (t(21) = 3.87; p < .001). Anterior MRCPs were similar between habitual and non-habitual grasping (t(21) = 0.98; n.s.). Furthermore, the mean amplitude of posterior MRCPs was negatively correlated with the reaction time for right-hand movements in the preparation of both habitual (r(20) = -0.45; p < .05) and non-habitual grasping (r(20) = -0.52; p < .05) but not for left-hand movements (all r(20)s < 0.1; n.s.).Our results suggest that movement preparation is affected by grasping habits. Instead of the anterior MRCPs, the posterior cortical activities during movement preparation are suggested to represent the grasping habits.

Perceptual performance, anticipating opponents' strategies, and judging chess positions especially in subliminal processing is related to expertise level and dependent on chunking processes. It becomes obvious that chess expertise is a multidimensional phenomenon related predominantly to experience. Under consideration of chess expertise categorization, we conducted two priming experiments expanding existing designs by gradually increasing the target and task complexity. The main aim was the evaluation of potential visuocognitive limitations. The results reveal experts' perceptual superiority manifested by their faster reaction times in settings with increased stimulus and task complexity. Further, experts' priming effects seem to be affected by the target content and/ or priming duration. For short prime duration, experts show priming effects only for less complex prime-target content. Interestingly, for longer prime duration and more complex prime-target content, all participants reveal priming effects. In summary, we argue that experts' visuocognitive processing (i.e., detecting or anticipating potential threats to the king) is rooted in a more efficient visuocognition due to stored chunks of checking and mating constellations. We suggest that visuocognitive limitations are related also to the prime-target complexity as well as to the task. Further investigations must be conducted in order to elucidate the factors with an increased impact on chess players' performance.

Major depressive disorder (MDD) is the most common mental disorder and deficits in neuroplasticity are discussed as one pathophysiological mechanism. Physical activity (PA) enhances neuroplasticity in healthy subjects and improves clinical symptoms of MDD. However, it is unclear whether this clinical effect of PA is due to restoring deficient neuroplasticity in MDD. We investigated the effect of a 3-week PA program applied on clinical symptoms, motor excitability and plasticity, and on cognition in patients with MDD (\(\it N\) = 23), in comparison to a control intervention (CI; \(\it N\) = 18). Before and after the interventions, the clinical symptom severity was tested using self- (BDI-II) and investigator- (HAMD-17) rated scales, transcranial magnetic stimulation (TMS) protocols were used to test motor excitability and paired-associative stimulation (PAS) to test long-term-potentiation (LTP)-like plasticity. Additionally, cognitive functions such as attention, working memory and executive functions were tested. After the interventions, the BDI-II and HAMD-17 decreased significantly in both groups, but the decrease in HAMD-17 was significantly stronger in the PA group. Cognition did not change notably in either group. Motor excitability did not differ between the groups and remained unchanged by either intervention. Baseline levels of LTP-like plasticity in the motor cortex were low in both groups (PA: 113.40 \(\pm\) 2.55%; CI: 116.83 \(\pm\) 3.70%) and increased significantly after PA (155.06 \(\pm\) 10.48%) but not after CI (122.01 \(\pm\) 4.1%). Higher baseline BDI-II scores were correlated with lower levels of neuroplasticity. Importantly, the more the BDI-II score decreased during the interventions, the stronger did neuroplasticity increase. The latter effect was particularly strong after PA (\(\it r\) = −0.835; \(\it p\) < 0.001). The level of neuroplasticity related specifically to the psychological/affective items, which are tested predominantly in the BDI-II. However, the significant clinical difference in the intervention effects was shown in the HAMD-17 which focuses more on somatic/neurovegetative items known to improve earlier in the course of MDD. In summary, PA improved symptoms of MDD and restored the deficient neuroplasticity. Importantly, both changes were strongly related on the individual patients' level, highlighting the key role of neuroplasticity in the pathophysiology and the clinical relevance of neuroplasticity-enhancing interventions for the treatment of MDD.

The goal of this study was to examine age and gender-related differences in quantitative and qualitative throwing performances of novices across a lifespan six to 16 years of age. Quantitative and qualitative throwing performances of 110 participants were evaluated in a controlled setting. The overall throwing movement was also sub divided into five essential movement characteristics: trunk, forearm, humerus, stepping, and backswing actions (Halverson & Roberton, 1984).The participants had to throw as hard and accurate as possible aiming a target on the wall. Each trial was videotaped for qualitative data analysis which has been conducted by using a modified component approach. The present findings show that across the three age bands, novices stagnated on a low level of movement development. Also, gender differences in the development of the throwing movement characteristics were found for the age band childhood and in some features gender differences were sustained throughout the examined age bands until adolescence. Within the novices, higher performance values in favour of male were found during childhood for trunk, forearm, and backswing actions, and in the quantitative performance-measure. Within the pubescence, gender differences existed only for trunk action and within the adolescence only for backswing action. There were no progress in throwing movement characteristics between the various levels of motor development. Thus, no improvement of the throwing movement quality and accuracy (quantity) could be recognised, which is calling for improvements in physical education. Compared with athletes in the same age, in contrast a study by Gromeier, Koester, and Schack (2017) show that with increasing age, qualitative performance of male and female athletes improves and furthermore it can be seen that male and female athletes demonstrated similar movement patterns in the main function phase. That raises questions concerns issue of physical education.

Communication between humans and computers is getting more and more relevant for all fields of our daily life. It is important to make this communication as intuitive and applicable as possible for all classes of population, independent of personal skills and abilities. Because human-computer interfaces are already involved in daily life actions it is necessary to find a method which is usable in everyday life and not only under laboratory conditions. Compared to existing FRP (fixation- related potentials) studies, we combined simultaneously recorded EEG with eye-tracking data to distinguish between task-relevant and irrelevant objects in a more natural environment. The experiment was done in an electrically shielded room by the measure of a 64 electrode EEG system combined and synchronized with a remote eye-tracker. The task was presented on a computer screen in front of the participants. The experiment consist of two conditions. A counting condition in which participants had to search for particular object classes, and an exploration condition in which the participants only had to explore the scene. The crowded scenes consist of at least two object categories with some similar features like shape or functionality, and additional background objects. We predict a significant difference in the brain activity by observing task relevant and irrelevant objects. Because the attention should be focused on task relevant objects, especially a higher P300 for this objects is assumed. Our experiments show that dependent on the fact an object is important for a given situation, the neurocognitive signature is different by observing relevant than irrelevant objects. Coming from a visible search task, the results show that for analysing FRPs, because of the novelty effect, it is enough to have one to three fixations on an object. The FRP component effects seem to decrease with every fixation on the same object. The FRPs are averaged potentials after each fixation onset on an object of task relevant or irrelevant object categories. A closer look to the affected brain areas shows that positive effects occur in frontal central regions by observing relevant objects. This, and also the time window of 350-700ms after fixation onset, is an indicator for a P300 component, and particular concerning the region, a P3a effect. The event-related potential component P3a is known as an indicator related to attention and processing novel stimuli. As summary it is shown that there is a higher cognitive effect by evaluating task relevant stimuli compared to non-relevant stimuli shown in a P3a. These findings can be used as basis for interaction designs for brain-computer interfaces (e.g. online classification algorithms).