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Introduction: Smartphones are often helpful in our everyday lives. Yet, they also tend to interrupt us during other activities. It has been argued that such distractions contribute to attention-deficit/hyperactivity disorder-like symptoms. However, since there are mostly correlational studies, the causal nature of this relationship is unclear. Our aim was to test whether reducing smartphone-related distractions might have a beneficial effect on inattention and hyperactive symptoms. Methods: We conducted a 1-week field experiment with 37 healthy undergraduates and quasi-randomly assigned them to an intervention or control group (CG). The intervention group was given theory-based specific instructions that aimed at reducing smartphone-related distractions, whereas the CG received no intervention. The outcomes of interest were inattention level, hyperactive symptoms, and working memory accuracy. Results: Compared to those in the control condition, participants who limited their smartphone use showed considerable reductions in hyperactive symptoms after 1 week – particularly those who displayed high problematic smartphone use. However, there were no group differences regarding inattention symptoms and working memory accuracy. Discussion: The results give a first hint that strategically reducing smartphone-related distractions via specific but simple use modifications can mitigate hyperactive symptoms. Especially people with problematic smartphone use seem to profit from such an intervention. Remaining questions and directions are discussed.

The self-concept—defined as the cognitive representation of beliefs about oneself—determines how individuals view themselves, others, and their actions. A negative self-concept can drive gaming use and internet gaming disorder (IGD). The assessment of the neural correlates of self-evaluation gained popularity to assess the self-concept in individuals with IGD. This attempt, however, seems to critically depend on the reliability of the investigated task-fMRI brain activation. As first study to date, we assessed test–retest reliability of an fMRI self-evaluation task. Test–retest reliability of neural brain activation between two separate fMRI sessions (approximately 12 months apart) was investigated in N = 29 healthy participants and N = 11 individuals with pathological internet gaming. We computed reliability estimates for the different task contrasts (self, a familiar, and an unknown person) and the contrast (self > familiar and unknown person). Data indicated good test–retest reliability of brain activation, captured by the “self”, “familiar person”, and “unknown person” contrasts, in a large network of brain regions in the whole sample (N = 40) and when considering both experimental groups separately. In contrast to that, only a small set of brain regions showed moderate to good reliability, when investigating the contrasts (“self > familiar and unknown person”). The lower reliability of the contrast can be attributed to the fact that the constituting contrast conditions were highly correlated. Future research on self-evaluation should be cautioned by the findings of substantial local reliability differences across the brain and employ methods to overcome these limitations.

Study Objectives Subjective reports of sleep impairments are common in individuals with posttraumatic stress disorder (PTSD), but objective assessments of sleep have yielded mixed results. Methods We investigated sleep via actigraphy and e-diary on 6 consecutive nights in a group of 117 women with PTSD after childhood abuse (CA; PTSD group), a group of 31 mentally healthy women with a history of CA (healthy trauma controls, HTC group) and a group of 36 nontraumatized mentally healthy women (healthy controls, HC group). Results The PTSD group reported lower sleep quality, more nights with nightmares, and shorter sleep duration than both HTC and HC. Actigraphic measures showed more and longer sleep interruptions in the PTSD group compared to HTC and HC, but no difference in sleep duration. While the PTSD group underestimated their sleep duration, both HTC and HC overestimated their sleep duration. HTC did not differ from HC regarding sleep impairments. Conclusions Sleep in women with PTSD after CA seems to be more fragmented but not shorter compared to sleep patterns of mentally healthy control subjects. The results suggest a stronger effect of PTSD psychopathology on sleep compared to the effect of trauma per se. Subset of Data from Clinical Trial Treating Psychosocial and Neural Consequences of Childhood Interpersonal Violence in Adults (RELEASE), https://www.drks.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00000000, German Clinical Trials registration number: DRKS00005578

Recent debates in the literature discuss commonalities between Attention-Deficit/Hyperactivity Disorder (ADHD) and Autism Spectrum Disorder (ASD) at multiple levels of putative causal networks. This debate requires systematic comparisons between these disorders that have been studied in isolation in the past, employing potential markers of each disorder to be investigated in tandem. The present study, choose superior local processing, typical to ASD, and increased Intra-Subject Variability (ISV), typical to ADHD, for a head-to-head comparison of the two disorders, while also considering the comorbid cases. It directly examined groups of participants aged 10–13 years with ADHD, ASD with (ASD+) or without (ASD−) comorbid ADHD and a typically developing (TD) group (total N = 85). A visual search task consisting of an array of paired words was designed. The participants needed to find the specific pair of words, where the first word in the pair was the cue word. This visual search task was selected to compare these groups on overall search performance and trial-to-trial variability of search performance (i.e., ISV). Additionally, scanpath analysis was also carried out using Recurrence Quantification Analysis (RQA) and the Multi-Match Model. Results show that only the ASD− group exhibited superior search performance; whereas, only the groups with ADHD symptoms showed increased ISV. These findings point towards a double dissociation between ASD and ADHD, and argue against an overlap between ASD and ADHD.

Objective To identify non-EEG-based signals and algorithms for detection of motor and non-motor seizures in people lying in bed during video-EEG (VEEG) monitoring and to test whether these algorithms work in freely moving people during mobile EEG recordings. Methods Data of three groups of adult people with epilepsy (PwE) were analyzed. Group 1 underwent VEEG with additional devices (accelerometry, ECG, electrodermal activity); group 2 underwent VEEG; and group 3 underwent mobile EEG recordings both including one-lead ECG. All seizure types were analyzed. Feature extraction and machine-learning techniques were applied to develop seizure detection algorithms. Performance was expressed as sensitivity, precision, F$_{1}$ score, and false positives per 24 hours. Results The algorithms were developed in group 1 (35 PwE, 33 seizures) and achieved best results (F$_{1}$ score 56%, sensitivity 67%, precision 45%, false positives 0.7/24 hours) when ECG features alone were used, with no improvement by including accelerometry and electrodermal activity. In group 2 (97 PwE, 255 seizures), this ECG-based algorithm largely achieved the same performance (F$_{1}$ score 51%, sensitivity 39%, precision 73%, false positives 0.4/24 hours). In group 3 (30 PwE, 51 seizures), the same ECG-based algorithm failed to meet up with the performance in groups 1 and 2 (F$_{1}$ score 27%, sensitivity 31%, precision 23%, false positives 1.2/24 hours). ECG-based algorithms were also separately trained on data of groups 2 and 3 and tested on the data of the other groups, yielding maximal F1 scores between 8% and 26%. Significance Our results suggest that algorithms based on ECG features alone can provide clinically meaningful performance for automatic detection of all seizure types. Our study also underscores that the circumstances under which such algorithms were developed, and the selection of the training and test data sets need to be considered and limit the application of such systems to unseen patient groups behaving in different conditions.

Measuring brain activity in moving subjects is of great importance for investigating human behavior in ecological settings. For this purpose, EEG measures are applicable, however, technical modifications are required to reduce the typical massive movement artefacts. Four different approaches to measure EEG/ERPs during rowing were tested: (i) a purpose-built head-mounted preamplifier, (ii) a laboratory system with active electrodes, and a wireless headset combined with (iii) passive or (iv) active electrodes. A standard visual oddball task revealed very similar (within subjects) visual evoked potentials for rowing and rest (without movement). The small intraindividual differences between rowing and rest, in comparison to the typically larger interindividual differences in the ERP waveforms, revealed that ERPs can be measured reliably even in an athletic movement such as rowing. On the other hand, the expected modulation of the motor-related activity by force output was largely affected by movement artefacts. Therefore, for a successful application of ERP measures in movement research, further developments to differentiate between movement-related neuronal activity and movement-related artefacts are required. However, activities with small magnitudes related to motor learning and motor control may be difficult to detect because they are superimposed by the very large motor potential, which increases with force output.

Research in memory reconsolidation has raised hope for new treatment options of persistent psychiatric disorders like substance dependence and post-traumatic stress disorder (PTSD). While animal research showed successful memory modification by interfering with reconsolidation, human research requires less invasive techniques. In our pilot study, we aimed to reduce appetitive memory reconsolidation of a newly acquired reward memory by exerting a stressor. Thirty healthy participants were randomly assigned to two groups performing a monetary reward paradigm at a personal computer. Day 1 was considered to allow for memory acquisition; on day 2, the experimental group was exposed to a frightening stimulus in the reconsolidation window; and day 3 again served to determine reward memory effects. Measures of reward memory were reaction times to reward announcing stimuli (ie, showing instrumental behavior), actual reward gained, and electrodermal response as a measure for reward anticipation. We found significantly smaller reaction time improvements to reward stimuli over time in the experimental group, as well as reduced achievements in monetary reward. Electrodermal response to reward announcing stimuli was lower in the experimental group after intervention, whereas it was higher in the untreated group. Thus, we argue in favor of the reconsolidation hypothesis, assuming our intervention had successfully interfered with the reconsolidation process. This points towards future treatment options that interfere with an addiction memory.

Background and aims Internet gaming addiction appears to be related to self-concept deficits and increased angular gyrus (AG)-related identification with one's avatar. For increased social network use, a few existing studies suggest striatal-related positive social feedback as an underlying factor. However, whether an impaired self-concept and its reward-based compensation through the online presentation of an idealized version of the self are related to pathological social network use has not been investigated yet. We aimed to compare different stages of pathological Internet game and social network use to explore the neural basis of avatar and self-identification in addictive use. Methods About 19 pathological Internet gamers, 19 pathological social network users, and 19 healthy controls underwent functional magnetic resonance imaging while completing a self-retrieval paradigm, asking participants to rate the degree to which various self-concept-related characteristics described their self, ideal, and avatar. Self-concept-related characteristics were also psychometrically assessed. Results Psychometric testing indicated that pathological Internet gamers exhibited higher self-concept deficits generally, whereas pathological social network users exhibit deficits in emotion regulation only. We observed left AG hyperactivations in Internet gamers during avatar reflection and a correlation with symptom severity. Striatal hypoactivations during self-reflection (vs. ideal reflection) were observed in social network users and were correlated with symptom severity. Discussion and conclusion Internet gaming addiction appears to be linked to increased identification with one's avatar, evidenced by high left AG activations in pathological Internet gamers. Addiction to social networks seems to be characterized by emotion regulation deficits, reflected by reduced striatal activation during self-reflection compared to during ideal reflection.

Background To translate highly accelerated EPI-fMRI protocols as commonly used at ultra-high field strengths to clinical 3 T settings. New method EPI protocols with increasing matrix sizes and parallel imaging (PI) factors were tested in two separate fMRI studies, a simple motor-task and a complex motivation-task experiment with focus on the sensorimotor cortex (SMC) and the nucleus accumbens (NAcc), respectively. Results By increasing the matrix size and the PI-factor simultaneously, BOLD-sensitivity in terms of maximal t -values and numbers of activated clusters was uncompromised in single individuals in both fMRI experiments. In the SMC, the multi-subject analysis revealed an increase of 66% of the maximal t -value whereby the number of activated clusters was increased by a factor of 3.3 when the matrix size (PI-factor) was increased from 96 × 96 ( R = 2) to 192 × 192 ( R = 4). In the NAcc, the number of activated clusters increased from 5 to 7 whereby the maximal t -value remained unaffected when the matrix size (PI-factor) was increased from 96 × 96 ( R = 2) to 160 × 160 ( R = 3). Comparison with existing method Using the proposed high-resolution EPI protocol, spatial blurring was clearly reduced. Further, BOLD sensitivity was clearly improved in multi-subject analyses and remained unaffected in single individuals compared to using the standard protocols. Conclusions Conventionally used matrix sizes (PI-factors) might be non-optimal for some applications sacrificing BOLD spatial specificity. We recommend using the proposed high-resolution protocols applicable in detecting robust BOLD activation in fMRI.

Aims MMORPG addiction has been associated with self-concept impairments and increased identification with the own avatar. Yet, the underlying neurobiological mechanisms of self-identification with avatars, especially reflected in the left angular gyrus (AG), have only been assessed in regular gamers. Therefore, the study aims to examine neurobiological processes in addicted MMORPG players while evaluating their own and their personal avatar's body image (physical self-concept). Methods Sixteen addicted and seventeen non-addicted gamers underwent functional Magnetic Resonance Imaging (fMRI) while viewing images of themselves, their own avatar and unfamiliar persons. The Body Image Questionnaire (FKB-20) and Visual Analog Scales (VAS) assessing the degree of attractiveness, sympathy and gender identity of the self, of the avatar as well as of the unfamiliar persons were applied. Results Addicts showed a significantly extended negative body image and lower gender identity levels as well as decreased bilateral brain activations in the AG and the middle occipital gyrus during self-perception. They further exhibited higher activations in the left AG during avatar-perception. Regression analyses in the overall group and in addicted gamers indicated a significant positive correlation between gender identity and brain activation in the left AG during self-perception. Conclusions Our results confirm addicted MMORPG players to have physical self-concept deficits which may be related to hypoactivations in the AG. The findings further indicate addicted gamers to have a tendency to identify themselves easier with their own avatar than with their real self. Lower gender identity levels might be associated with physical self-concept deficits in MMORPG addiction.

Performance on tasks requiring discrimination of at least two stimuli can be viewed either from an objective perspective (referring to actual stimulus differences), or from a subjective perspective (corresponding to participant’s responses). Using event-related potentials recorded during an old/new recognition memory test involving emotionally laden and neutral words studied either blockwise or randomly intermixed, we show here how the objective perspective (old versus new items) yields late effects of blockwise emotional item presentation at parietal sites that the subjective perspective fails to find, whereas the subjective perspective (“old” versus “new” responses) is more sensitive to early effects of emotion at anterior sites than the objective perspective. Our results demonstrate the potential advantage of dissociating the subjective and the objective perspective onto task performance (in addition to analyzing trials with correct responses), especially for investigations of illusions and information processing biases, in behavioral and cognitive neuroscience studies.

The present study investigated changes in frontal and parietal activity related to visuomotor learning. Improvement in task performance should be achieved by a transition from feedback control to feedforward control. Event-related potential (ERP) activity related to visual feedback analysis of successful error corrections was expected to decrease at parietal scalp locations. (Pre-) motor activity related to the execution of directional changes should increase and begin earlier. While using a mouse or a joystick for cursor control, subjects performed four different conditions of a pursuit tracking task in a between-subject design. To increase task difficulty, and to set up an implicit learning condition, the gain between mouse/joystick movement and cursor movement increased during the middle of each tracking trial. Subjects were informed about this manipulation in the explicit task only. Within the continuous movement of 12 s duration, ERPs were assigned to phasic changes of target and cursor direction. Visuomotor learning was mainly achieved by a continuous reduction of target and cursor distance. A fronto-central positive ERP component related to the execution of a directional change increased earlier after learning. This indicates an anticipated directional change, improving task performance. ERP activity after error corrections decreased after learning, indicating either a higher efficiency or a reduced demand in visual feedback control. Activity difference was shifted from parietal to fronto-central sites later indicating a relation to improved feedforward control. No clear difference between implicit and explicit learning was observed for behavioural and ERP data.

In competitive rowing, the fluctuations in boat velocity during the rowing cycle are associated with an increased water resistance of the boat as compared with a boat moving at a constant velocity. We aimed to quantify the influence of the increased water resistance on race time using a mathematical approximation, based on the increase in physiological power being proportional to the 2nd power of boat speed. Biomechanical data (oar force, rowing angle, boat velocity, and boat acceleration) were measured when eight elite coxless pair crews performed a rowing test with a stepwise increasing stroke rate (SR: 20, 24, 28, and 32 min(-1)) that successively increased the mean boat speed. The results revealed a +4.59 s (SR 24.2) to +5.05 s (SR 31.5) 2000-m race-time difference compared with a boat hypothetically moving without velocity fluctuations. Velocity fluctuations were highly correlated with SR (r=0.93) because the accelerations of the rowers' body mass and the mass of the counteracting boat increase with SR. The possibilities to reduce velocity fluctuations and therefore race time are limited. For elite rowers, race time may be slightly reduced by a moderate reduction in SR that is compensated by an increased force output for each stroke.

Background Abnormalities in motor activity represent a central feature in major depressive disorder. However, measurement issues are poorly understood, limiting the use of objective measurement of motor activity for diagnostics and treatment monitoring. Methods To improve measurement issues, especially sensor placement, analytic strategies and diurnal effects, we assessed motor activity in depressed patients at the beginning (MD; n=27) and after anti-depressive treatment (MD-post; n=18) as well as in healthy controls (HC; n=16) using wrist- and chest-worn accelerometers. We performed multiple analyses regarding sensor placements, extracted features, diurnal variation, motion patterns and posture to clarify which parameters are most powerful in distinguishing patients from controls and monitoring treatment effects. Results Whereas most feature-placement combinations revealed significant differences between groups, acceleration (wrist) distinguished MD from HC (d=1.39) best. Frequency (vertical axis chest) additionally differentiated groups in a logistic regression model (R2=0.54). Accordingly, both amplitude (d=1.16) and frequency (d=1.04) showed alterations, indicating reduced and decelerated motor activity. Differences between MD and HC in gestures (d=0.97) and walking (d=1.53) were found by data analysis from the wrist sensor. Comparison of motor activity at the beginning and after MD-treatment largely confirms our findings. Limitations Sample size was small, but sufficient for the given effect sizes. Comparison of depressed in-patients with non-hospitalized controls might have limited motor activity differences between groups. Conclusions Measurement of wrist-acceleration can be recommended as a basic technique to capture motor activity in depressed patients as it records whole body movement and gestures. Detailed analyses showed differences in amplitude and frequency denoting that depressed patients walked less and slower.

In a case study, Schaffert and Mattes reported the application of acoustic feedback (sonification) to optimise the time course of boat acceleration. The authors attributed an increased boat speed in the feedback condition to an optimised boat acceleration (mainly during the recovery phase). However, in rowing it is biomechanically impossible to increase the boat speed significantly by reducing the fluctuations in boat acceleration during the rowing cycle. To assess such a, potentially small, optimising effect experimentally, the confounding variables must be controlled very accurately (that is especially the propulsive forces must be kept constant between experimental conditions or the differences in propulsive forces between conditions must be much smaller than the effects on boat speed resulting from an optimised movement pattern). However, this was not controlled adequately by the authors. Instead, the presented boat acceleration data show that the increased boat speed under acoustic feedback was due to increased propulsive forces.

The aim of this study was to investigate the event-related potential correlates of response inhibition in the N2 time window, specifically in the auditory modality. A paired tone Go/Nogo paradigm elicited an enhanced fronto-central negativity in the Nogo condition, which was accompanied by a concurring inferior fronto-temporal positivity. In contrast to most previous studies our data provide evidence for a fronto-central Nogo-N2 component in the auditory modality.

A common hypothesis about sex differences in language processing attributes these differences to a bilateral contribution of language-related brain areas in females and a left-hemispheric dominated activation in males. However, most imaging studies failed to find such a generalized lateralization effect and reported a left-lateralized activation in both sexes instead. In a previous semantic priming study, we found a sustained (approximately 190-640 ms) bilateral positivity in the ERP waveforms, which was larger for the female group. Word reading and lexical decision were confounded in that study. In the present study we used a delayed response to separate semantic processing from response selection and execution. The modification of the task design, together with a dense sensor array, showed that females developed a bilateral sustaining posterior positivity/frontal negativity during reading/semantic processing. In contrast, males showed an attenuated positivity at left posterior sites and an attenuated negativity at right frontal sites. This sex-specific lateralization effect disappeared during response processing, evoking a bilaterally distributed activation for both sexes (frontal negative and posterior positive), which was larger for the female subjects. We conclude that, at least under specific conditions, language processing evokes a bilateral activation in females and a lateralization effect in males. However, the processing of the response, which is dominated by a 'P300-like' component evoked by this process, evokes a larger activation in both sexes which obscures the sex-specific lateralization effect when semantic processing and response processing are not separated.

Semantic network models propose that automatic (e.g. spreading activation) and controlled processes are involved in semantic priming. Behavioural studies propose that the influence of each of these processes depends on the stimulus onset asynchrony (SOA). To investigate this hypothesis with a more sensitive method, we applied high-resolution event-related potential (ERP) measures to a word-pseudoword lexical decision task that contained direct, indirect, and non-related prime-target pairs. SOAs consisted of 150 or 700 ms. The results showed that independently of SOA, increasing semantic distance prolonged reaction times and enlarged N400 amplitudes. Furthermore, the word-pseudoword decision evoked a parieto-central late positive complex (LPC respectively delayed P300), which was sensitive for semantic relatedness in the short SOA only. In addition, we found two early frontal components: a P250 in the short SOA only and a N310 sensitive to semantic relatedness more prominent in the short SOA. We conclude that ERP-differences between both SOAs indicate two separate processes: (1) an access to semantic memory, which is facilitated by spreading activation in the short SOA only; and (2) an SOA-independent, controlled process, which integrates prime and target words into a semantic context.

Psychometric studies suggest that observed self-concept deficits in addicted massively multiplayer online role-playing game (MMORPG) are compensated through the replacement of their ideal (i.e., how an individual would like to be) by their own avatar (i.e., graphical agent in the virtual world). Neurobiological studies indicate that increased identification with their own avatar in regular MMORPG gamers is possibly reflected by enhanced avatar-referential brain activation in the left angular gyrus (AG). However, the neurobiological correlates reflecting the relations of the avatar to addicted gamers' self and ideal are still unexplored. Therefore, we compare these relations between addicted and nonaddicted MMORPG gamers. A sample of n = 15 addicted and n = 17 nonaddicted players underwent functional MRI (fMRI) while completing a Giessen-Test (GT)-derived paradigm assessing self-, ideal-, and avatar-related self-concept domains. Neurobiological analyses included the comparisons avatar versus self, avatar versus ideal, and avatar versus self, ideal. Psychometrically, addicts showed significantly lower scores on the self-concept subscale of 'social resonance,' that is, social popularity. In all avatar-related contrasts, within-group comparisons showed addicted players to exhibit significantly higher brain activations in the left AG. The between-groups comparisons revealed avatar-related left AG hyperactivations in addicts. Our results may suggest that addicted MMORPG players identify significantly more with their avatar than nonaddicted gamers. The concrete avatar might increasingly replace the rather abstract ideal in the transition from normal- controlled to addictive-compulsive MMORPG usage.

Previous research on alcohol dependent patients has shown that variations in eyeblink startle response can be used as an indicator of their emotional responses to alcohol-related stimuli. Postulating that reactions on substance associated stimuli are controlled by either a negative or a positive affective processing system, we expect that abstinent alcoholics react differently (within-group) in the emotional evaluation of alcohol cues. Furthermore, we assumed the startle response to covary with medication response to acamprosate and naltrexone. We measured 74 detoxified inpatients' acoustic startle responses while they were being presented with alcohol-related images as well as affectively negative, neutral, and positive pictures before they were randomized to pharmacotherapy. Group-mean startle peak amplitudes were lowest for alcohol-related cues. The relative startle response (alcohol cues set in relation to the other stimulus categories) did not correlate with craving for alcohol (OCDS) or alcohol cue induced self-ratings of arousal, valence and craving. Patients with a lower percentage of abstinent days in the 90 days prior to the last drinking day showed a lower ("more appetitive") startle response to alcohol cues. A survival analysis using the time to first heavy drinking day as the survival criterion revealed a significant interaction between alcohol-cue startle responses and medication type. The results indicate that the psycho-physiological measure of emotional evaluation of alcohol cues includes unconscious processing not reflected by conscious self-ratings. Furthermore, our result of a differential medication effect may encourage further studies to use biological characteristics to stratify patients as a step towards individualized treatment for alcohol dependence.

Background: While the majority of depressed patients benefit from total sleep deprivation (TSD), light therapy is regarded as a first-line treatment only for seasonal affective disorder (SAD). The results of light therapy in nonseasonal major depressive disorder have been non-conclusive. We examined the correlation of TSD response and light therapy response in major depressed patients. Methods: 40 inpatients with major depressive disorder (seven with seasonal pattern, 33 without seasonal pattern) were deprived of a night’s sleep. The TSD responders, as well as the TSD nonresponders, were randomly assigned to receive adjunct light therapy either with bright white light (2500 lux) or dim red light (50 lux) during 2 weeks beginning on the third day after TSD. Results: The 20 TSD responders improved significantly better under the light therapy than the 20 TSD nonresponders (according to the Hamilton Depression Rating Scale and the self-rating depression scale Bf-S; v. Zerssen). Limitations: No significant difference could be found between the two light intensities. Since the patients were additionally treated with medication an interaction with the two adjunctive therapies cannot be excluded. Conclusion: Our results indicate that a positive TSD response in major depressed patients can be predicative of beneficial outcome of subsequent light therapy.

Objectives : A general reduction of auditory P300 amplitude is one of the most consistently replicated observations in schizophrenic patients. However, a left hemisphere amplitude reduction is discussed controversely. Methods : Encouraged by this controversy we analysed P300 data of 53 controls and 60 patients of the schizophrenia spectrum (ICD-10: F20, F23, F25). Results : Our main result was the finding of the correlation between general amplitude and hemispheric asymmetry in the patient group: low general amplitudes were assigned to a left hemispheric amplitude reduction, high amplitudes to a right hemispheric reduction. Based on this result, we grouped all subjects according to their hemispheric asymmetry pattern. The control group and the group of schizoaffective patients (F25) with a left hemispheric amplitude reduction showed the inverse asymmetry pattern of P300 amplitude compared to subjects with a right hemispheric amplitude reduction. In contrast, the schizophrenic patients (F20) showed only a difference in P300 amplitudes measured at electrode sites of the left hemisphere. Additionally, we could show, that the amount of the general amplitude reduction in patients was different between the diagnostic groups. Conclusions : We conclude that a left hemispheric amplitude reduction is not a general feature of schizophrenia but it seems to be pathological when combined with a general amplitude reduction.

A novel ERP paradigm was employed to investigate conceptual expansion, a central component of creative thinking. Participants were presented with word pairs, consisting of everyday objects and uses for these objects, which had to be judged based on the two defining criteria of creative products: unusualness and appropriateness. Three subject-determined trial types resulted from this judgement: high unusual and low appropriate (nonsensical uses), low unusual and high appropriate (common uses), and high unusual and high appropriate (creative uses). Word pairs of the creative uses type are held to passively induce conceptual expansion. The N400 component was not specifically modulated by conceptual expansion but was, instead, generally responsive as a function of unusualness or novelty of the stimuli (nonsense=creative>common). Explorative analyses in a later time window (500–900 ms) revealed that ERP activity in this phase indexes appropriateness (nonsense>creative=common). In the discussion of these findings with reference to the literature on semantic cognition, both components are proposed as indexing processes relevant to conceptual expansion as they are selectively involved in the encoding and integration of a newly established semantic connection between two previously unrelated concepts.

Conceptual expansion, one of the core operations in creative cognition, was investigated in the present ERP study. An experimental paradigm using novel metaphoric, nonsensical and literal phrases was employed where individual differences in conceptual knowledge organization were accounted for by using participants' responses to categorize the stimuli to each condition. The categorization was determined by their judgment of the stimuli on the two defining criteria of creativity: unusualness and appropriateness. Phrases judged as unusual and appropriate were of special interest as they are novel and unfamiliar phrases thought to passively induce conceptual expansion. The results showed a graded N400 modulation for phrases judged to be unusual and inappropriate (nonsense) or unusual and appropriate (conceptual expansion, novel metaphorical) relative to usual and appropriate (literal) phrases. The N400 is interpreted as indexing greater effort to retrieve semantic information and integrate the novel concepts presented through the phrases. Analyses of the later time-window showed an ongoing negativity that was graded in the same manner as the N400. The findings attest to the usefulness of investigating creative cognition using event-related electrophysiology.

Based on a previous exploratory study, the functionality of event-related potentials related to visuomotor processing and learning was investigated. Three pursuit tracking tasks (cursor control either mouse, joystick, or bimanually) revealed the greatest tracking error and greatest learning effect in the bimanual task. The smallest error without learning was found in the mouse task. Error reduction reflected visuomotor learning. In detail, target-cursor distance was reduced continuously, indicating a better fit to a changed direction, whereas response time remained at 300 ms. A central positive ERP component with an activity onset 100 ms after a directional change of the target and most likely generated in premotor areas could be assigned to response planning and execution. The magnitude of this component was modulated by within-and-between-task difficulty and size of the tracking error. Most importantly, the size of this component was sensitive to between-subject performance and increased with visuomotor learning.

The aim of this single-blind randomized crossover study was to evaluate specific effects of manual acupuncture on central and vegetative nervous system activity measured by quantitative electroencephalography (qEEG) and heart rate variability (HRV).Twenty (20) healthy volunteers (mean: 25.2 +/- 3.6 years) were monitored simultaneously using a qEEG system and a 12-channel electrocardiogram recorder during verum acupuncture (VA) at acupuncture point Large Intestine 4 (Hegu) (LI4) or placebo acupuncture (PA) at a sham point.In the EEG conduction of the occipital area, needle stimulation in VA increased alpha1-frequency significantly, and the ratio alpha1/theta was shifted to the benefit of alpha1 over all electrodes. The HRV parameters showed a significant increase of the low frequency/high frequency (HF) ratio during the first minute of stimulation in VA, indicating an initial increase of sympathetic activation. However, an increase of HF power in the minute after stimulation followed by a decrease in heart rate suggests delayed vagal activation. De qi (a sensation that is typical of acupuncture needling) occurred in 16 subjects during VA and in 9 volunteers during PA (80% versus 45%).Manual stimulation on LI4 seems to lead to specific changes in alpha EEG-frequency and in HRV parameters. A linear relationship between the HRV parameters and the alpha EEG band might point to a specific modulation of cerebral function by vegetative effects during acupuncture.

Non-invasive techniques such as neuroimaging and event-related potential (ERP) methods have dramatically enhanced our understanding of the human brain. According to the requirements of the applied method, it is useful to simplify tasks for methodological reasons. In the present study we tested whether ERP measures are also suitable for analyzing complex tasks. In order to do this, we developed an analysis strategy based on the post hoc analysis of the behavioural data. We applied this method to a pursuit-tracking task of 25 s trial duration, consisting of repeated and non-repeated waveforms, where subjects had to track a target cross with a mouse-controlled cursor cross. An EEG was recorded from 62 channels. Response-locked ERPs were computed for two types of error correction: the correction of errors induced externally by the change of target direction and of internal errors generated by the subject itself. We found several ERP components that could be assigned to different feedback and feedforward controlled processing steps in the frontoparietal circuitry underlying visuomotor control, such as movement planning, movement execution (motor potential), reafferent activity, visuospatial analysis, and attentional (P300) processes. Our results support newer models that propose a role for the posterior parietal cortex in integrating multimodal sensory information. In addition, fast (about 180 ms and probably facilitated by anticipation) and slow (about 230-260 ms) error corrections could be differentiated by the time course of ERP activity. Our results show that complex (motor) tasks can be investigated with ERPs. This opens fruitful perspectives for future research on motor control in an ecological setting.

For a rowing crew to be successful, the movements of the rowers need to be well coordinated. Because rowers show individual force patterns, they have to adapt their movements when rowing as a crew. In this exploratory study, these hypothesized changes in movement pattern were examined. The force graphs of six elite coxless fours crews were recorded over 11 training runs using strain gauges attached to the oars. A detailed force analysis showed that form differences, but not area differences, between force patterns decreased when force output increased as a result of two different processes. First, increasing force output reduced form differences instantaneously by reducing the individual variation in force patterns. Secondly, the kinaesthetic perception of form differences is easier than that of area differences. This better perception facilitates the adaptation of movement patterns, especially when force output is high.

The general reduction of P300 amplitude in response to auditory oddball stimuli is one of the most consistently replicated biological observations in schizophrenic patients. Several groups have reported a P300 asymmetry in schizophrenic patients, others have not been able to replicate this finding. In order to clarify this issue, we examined the effect of stimulus discriminability on P300 amplitude distribution in schizophrenic patients and in age-matched normal control subjects, using two different auditory oddball paradigms. The detection of the target tone was either simple or difficult, due to manipulation of pitch disparity. The P300 amplitude was comparatively smaller in the schizophrenic patient group compared to the healthy controls and in the difficult task compared to the simple. The schizophrenic patients showed a specific P300 amplitude reduction over left temporal electrode sites when the simple paradigm was used. The difficult paradigm did not elicit asymmetrical P300 amplitudes in schizophrenic patients.