Highlights • Task switching recruits the locus coeruleus. • Hippocampus and parahippocampal gyrus are engaged by learnable stimulus–response associations. • Performance monitoring and response ...adaptation involve partially overlapping brain networks.
We report on the long-term clinical outcome (up to 8 years) of 5 patients who received deep brain stimulation (DBS) of the nucleus accumbens to treat their long-lasting and treatment-resistant ...alcohol addiction. All patients reported a complete absence of craving for alcohol; 2 patients remained abstinent for many years and 3 patients showed a marked reduction of alcohol consumption. No severe or long-standing side effects occurred. Therefore, DBS could be a promising, novel treatment option for severe alcohol addiction, but larger clinical trials are needed to further investigate the efficacy of DBS in addiction.
Job-anxiety, as distinguished from trait-anxiety, is associated with long-term sickness absence. The prevalence of job-anxiety within a working population is not known. Identifying individuals who ...would benefit from intervention might be useful.
To investigate job-anxiety in employees not undergoing treatment for mental health illness, firstly by assessing the level of job-anxiety and work-related avoidance tendencies in a working sample, and secondly by testing whether job-anxiety is distinguishable from trait-anxiety.
Cross-sectional survey of a convenience sample obtained through personal contact distribution. Employees from different professional settings completed an anonymous questionnaire and provided information on their employment status. The State-Trait-Anxiety Inventory (STAI-T) was used to measure trait-anxiety and the Job-Anxiety-Scale (JAS) was used to assess job (state) anxiety.
There was a 69% response rate (240 responses); 188 responses were available for analysis of whom 62% were women. There were no employees with high trait-anxiety. Ten employees (5%) reported increased job-anxiety and of these nine employees reported high 'tendencies of avoidance and workplace absence'. Avoidance was most often accompanied by the comorbid job-anxieties 'job-related social anxiety', 'fear of changes at work' and 'fears of existence', 'anticipatory' and 'conditioned' job-anxiety and 'panic symptoms'.
In this sample, self-reported job-anxiety appeared as a specific type of anxiety as opposed to trait-anxiety. In the workplace job-anxiety can present as job-avoidance and sickness absence and should be distinguished from trait-anxiety. In practice, employers and occupational health practitioners should be aware of those employees prone to sickness absence.
The present study used event-related brain potentials (ERPs) to investigate audiovisual integration processes in the perception of natural speech in a group of German adult developmental dyslexic ...readers. Twelve dyslexic and twelve non-dyslexic adults viewed short videos of a male German speaker. Disyllabic German nouns served as stimulus material. The auditory and the visual stimulus streams were segregated to create four conditions: in the congruent condition, the spoken word and the auditory word were identical. In the incongruent condition, the auditory and the visual word (i.e., the lip movements of the utterance) were different. Furthermore, on half of the trials, white noise (45 dB SPL) was superimposed on the auditory trace. Subjects had to say aloud the word they understood after they viewed the video. Behavioral data. Dyslexic readers committed more errors compared to normal readers in the noise conditions, and this effect was particularly present for congruent trials. ERPs showed a distinct N170 component at temporo-parietal electrodes that was smaller in amplitude for dyslexic readers. Both, normal and dyslexic readers, showed a clear effect of noise at centro-parietal electrodes between 300 and 600 ms. An analysis of error trials reflecting audiovisual integration (verbal responses in the incongruent noise condition that are a mix of the visual and the auditory word) revealed more positive ERPs for dyslexic readers at temporo-parietal electrodes 200-500 ms poststimulus. For normal readers, no such effect was present. These findings are discussed as reflecting increased effort in dyslexics under circumstances of distorted acoustic input. The superimposition of noise leads dyslexics to rely more on the integration of auditory and visual input (lip reading). Furthermore, the smaller N170-amplitudes indicate deficits in the processing of moving faces in dyslexic adults. (Orig.).
Background and purpose
X‐linked dystonia‐parkinsonism (XDP) is an inherited neurodegenerative adult‐onset movement disorder associated with striatal atrophy. As the dopaminergic system has not yet ...been systemically studied in this basal ganglia model disease, it is unclear whether nigrostriatal dysfunction contributes to parkinsonism in XDP.
Methods
Pre‐ and post‐synaptic dopaminergic function was assessed in XDP. A total of 10 123jod‐benzamide (IBZM) single‐photon emission computed tomography (SPECT) images were obtained for nine patients aged 42.3 ± 9.5 years (SD; range 30–52) and one asymptomatic mutation carrier (38 years), and four ioflupane (FP‐CIT) SPECT images were obtained for four patients, aged 41.5 ± 11.6 years (range 30–52 years). Structural magnetic resonance imaging was also performed for all mutation carriers and 10 matched healthy controls.
Results
All patients were men who suffered from severe, disabling segmental or generalized dystonia and had varying degrees of parkinsonism. IBZM SPECT images were pathological in 8/9 symptomatic patients with distinct reduced post‐synaptic tracer uptake in the caudate nucleus and putamen, and unremarkable in the asymptomatic mutation carrier. Longer disease duration was correlated with lower IBZM binding ratios. All subjects exhibited slightly reduced FP‐CIT uptake values compared to controls for each analyzed region (−37% to −41%) which may be linked to basal ganglia volume loss. Visual inspection revealed physiological FP‐CIT uptake in 1/4 patients.
Conclusions
This nuclear imaging study provides evidence that the functional decline of post‐synaptic dopaminergic neurotransmission is related to disease duration and ongoing neurodegeneration. Given the severe striatal cell loss which could be verified with post‐synaptic nuclear imaging, both parkinsonism and dystonia in XDP are probably mainly due to striatal dysfunction.
Hypo‐ and hyperthyroidism have effects on brain structure and function, as well as cognitive processes, including memory. However, little is known about the influence of thyroid hormones on brain ...perfusion and the relationship of such perfusion changes with cognition. The present study aimed to demonstrate the effect of short‐term experimental hyperthyroidism on brain perfusion in healthy volunteers and to assess whether perfusion changes, if present, are related to cognitive performance. It is known that an interaction exists between brain perfusion and cerebral oxygen consumption rate and it is considered that neural activation increases cerebral regional perfusion rate in brain areas associated with memory. Measuring cerebral blood flow may therefore represent a proxy for neural activity. Therefore, arterial spin labelling (ASL) measurements were conducted and later analysed to evaluate brain perfusion in 29 healthy men before and after ingesting thyroid hormones for 8 weeks. Psychological tests concerning memory were performed at the same time‐points and the results were correlated with the imaging results. In the hyperthyroid condition, perfusion was increased in the posterior cerebellum in regions connected with cerebral networks associated with cognitive control and the visual cortex compared to the euthyroid condition. In addition, these perfusion changes were positively correlated with changes of performance in the German version of the Auditory Verbal Learning Task AVLT, Verbaler Lern‐und‐Merkfähigkeits‐Test (VLMT). Cerebellar perfusion and function therefore appears to be modulated by thyroid hormones, likely because the cerebellum hosts a high number of thyroid hormone receptors.
Abstract
Background
Increasing familiarity and practice might free up mental resources during laparoscopic surgical skills training. The aim of the study was to track changes in mental resource ...allocation during acquisition of laparoscopic surgical skills.
Methods
Medical students with no previous experience in laparoscopic surgery took part in a 5-week laparoscopic training curriculum. At the beginning and end of the training period, one of the training tasks was combined with a secondary auditory detection task that required pressing a foot switch for defined target tones, creating a dual-task situation. During execution of the two concurrent tasks, continuous electroencephalographic measurements were made, with special attention to the P300 component, an index of mental resources. Accuracy and reaction times of the secondary task were determined.
Results
All 14 participants successfully completed the training curriculum. Target times for successful completion of individual tasks decreased significantly during training sessions (P <0.001 for all tasks). Comparing results before and after training showed a significant decrease in event-related brain potential amplitude at the parietal electrode cluster (P300 component, W = 67, P = 0.026), but there were no differences in accuracy (percentage correct responses: W = 48, P = 0.518) or reaction times (W = 42, P = 0.850) in the auditory detection task.
Conclusion
The P300 decrease in the secondary task over training demonstrated a shift of mental resources to the primary task: the surgical exercise. This indicates that, with more practice, mental resources are freed up for additional tasks.
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