Interference during the implicit learning of two different motor sequences

It has been demonstrated that learning a second motor task after having learned a first task may interfere with the long-term consolidation of the first task. However, little is known about immediate changes in the representation of the motor memory in the early acquisition phase within the first minutes of the learning process. Therefore, we investigated such early interference effects with an implicit serial reaction time task in 55 healthy subjects. Each subject performed either a sequence learning task involving two different sequences, or a random control task. The results showed that learning the first sequence led to only a slight, short-lived interference effect in the early acquisition phase of the second sequence. Overall, learning of neither sequence was impaired. Furthermore, the two processes, sequence-unrelated task learning (i.e. general motor training) and the sequence learning itself did not appear to interfere with each other. In conclusion, although the long-term consolidation of a motor memory has been shown to be sensitive to other interfering memories, the present study suggests that the brain is initially able to acquire more than one new motor sequence within a short space of time without significant interferenc

CBT Reduces CBF

Background: Imaging studies have provided evidence that cognitive‐behavioral therapy (CBT ) is able to change brain activation in phobic patients in response to threatening stimuli. The changes occurred in both emotion‐generating and modulatory regions. In this study, we use a data‐driven approach to explore resting state cerebral blood flow (CBF ) measured by arterial spin labeling (ASL ), before and after CBT. Methods: Eight female patients with spider phobia were scanned before and 1 month after an exposure‐based group therapy for spider phobia. Each MRI session consisted of an ASL resting state measurement acquired before and after a symptom provocation task involving the showing of spider pictures in the scanner. The first ASL acquisition measured anticipatory anxiety and the second measured postprocessing of phobia‐relevant stimuli. Results: Cognitive‐behavioral therapy significantly reduced spider phobic symptoms in all patients. Symptom reduction during anticipatory anxiety was accompanied by reduced bilateral CBF in the parahippocampal gyrus, ventral anterior thalamus, Brodmann area 8, and the anterior cingulate cortex. During postprocessing of phobia‐relevant stimuli, patients showed reduced CBF in the bilateral insula, components of the motor cortex, and areas associated with language functions. Conclusions: Longitudinal CBF dynamics following CBT were in concordance with results from several studies using BOLD fMRI to investigate the effects of psychotherapy on brain activity. CBF can be quantified by ASL , with the principal advantage of sensitivity to slow variations in neural activity and task independence. Therefore, ASL may be a suitable method for monitoring and evaluating the efficacy of psychotherapy or pharmacotherapy approaches

Quantification of Network Perfusion in ASL Cerebral Blood Flow Data with Seed Based and ICA Approaches

Independent component analysis (ICA) or seed based approaches (SBA) in functional magnetic resonance imaging blood oxygenation level dependent (BOLD) data became widely applied tools to identify functionally connected, large scale brain networks. Differences between task conditions as well as specific alterations of the networks in patients as compared to healthy controls were reported. However, BOLD lacks the possibility of quantifying absolute network metabolic activity, which is of particular interest in the case of pathological alterations. In contrast, arterial spin labeling (ASL) techniques allow quantifying absolute cerebral blood flow (CBF) in rest and in task-related conditions. In this study, we explored the ability of identifying networks in ASL data using ICA and to quantify network activity in terms of absolute CBF values. Moreover, we compared the results to SBA and performed a test-retest analysis. Twelve healthy young subjects performed a fingertapping block-design experiment. During the task pseudo-continuous ASL was measured. After CBF quantification the individual datasets were concatenated and subjected to the ICA algorithm. ICA proved capable to identify the somato-motor and the default mode network. Moreover, absolute network CBF within the separate networks during either condition could be quantified. We could demonstrate that using ICA and SBA functional connectivity analysis is feasible and robust in ASL-CBF data. CBF functional connectivity is a novel approach that opens a new strategy to evaluate differences of network activity in terms of absolute network CBF and thus allows quantifying inter-individual differences in the resting state and task-related activations and deactivation

Burnout - das Zusammenspiel von Stress-Symptomen und Stress-Biomarkern

Einleitung Stressbedingte Erkrankungen, wie z.B. Burnout oder mittelgradige depressive Episode, sind geprägt von Symptomen der Erschöpfung, Depression, Angst sowie somatischen Beschwerden. Stressverarbeitungsstörungen zeigen sich zudem durch Veränderungen in unterschiedlichen physiologischen Parametern. Dazu gehören biologische Marker des vegetativen Nervensystems (z.B. Herzratenvariabilität (HRV)) und der neuronalen Plastizität (z.B. brain-derived neurotrophic factor (BDNF)). In dieser Studie ging es darum, zu zeigen, wie eine Verbesserung der subjektiven Stresssymptome nach erfolgreicher Therapie mit einem spezialisierten Behandlungskonzept mit Veränderungen in biologischen Markern von Stress assoziiert ist. Methode Es wurden 74 Patienten mit einer psychiatrischen Diagnose (F32.x (N=42), F33.x (N=29), F4 (N=3)) im Rahmen einer Stressverarbeitungsstörung (Burnout) eingeschlossen, die in stationärer Behandlung mit einem multimodalen Therapieansatz waren. Bei Ein- und Austritt (Dauer des Aufenthalts: 6-8 Wochen) wurden ihnen Fragebögen, z.B. zu Burnout- und Depressionssymptomen, abgegeben sowie die HRV im Schlaf und der BDNF-Spiegel im Blut gemessen. Ergebnisse / Schlussfolgerung Nach dem stationären Aufenthalt zeigte sich bei den Patienten eine signifikante Reduktion der Burnout- und Depressionssymptomatik sowie eine Verbesserung der Schlafqualität. Diese subjektive Verbesserung der Stresssymptome korrelierte deutlich mit einer Erhöhung des BDNF-Spiegels. Die HRV, bzw. die Parasympathikusaktivität im Schlaf zeigte keine signifikante Veränderung. Die Wirkung einer erfolgreichen Therapie scheint sich somit relativ schnell auf der Ebene der neuronalen Plastizität zu zeigen. Es wurde mehrfach belegt, dass eine moderate sportliche Betätigung sich besonders günstig auf den BDNF-Spiegel auswirkt. Das spricht somit für die Wirksamkeit des angewendeten, auf stressbedingte Erkrankungen spezialisierten Therapiekonzepts, das mehrere körperlich aktivierende Elemente integriert, welche die BDNF-Spiegelerhöhung mitunterstützt haben könnten. Dass am Ende des stationären Aufenthaltes bei den Patienten keine Veränderung in der Schlaf-HRV gezeigt werden konnte, weist darauf hin, dass neurovegetative Anpassungen längere Perioden der Erholung und des Stressmanagements beanspruchen könnten

CBT reduces CBF: cognitive-behavioral therapy reduces cerebral blood flow in fear‐relevant brain regions in spider phobia

Background Imaging studies have provided evidence that cognitive-behavioral therapy (CBT) is able to change brain activation in phobic patients in response to threatening stimuli. The changes occurred in both emotion-generating and modulatory regions. In this study, we use a data-driven approach to explore resting state cerebral blood flow (CBF) measured by arterial spin labeling (ASL), before and after CBT. Methods Eight female patients with spider phobia were scanned before and 1 month after an exposure-based group therapy for spider phobia. Each MRI session consisted of an ASL resting state measurement acquired before and after a symptom provocation task involving the showing of spider pictures in the scanner. The first ASL acquisition measured anticipatory anxiety and the second measured postprocessing of phobia-relevant stimuli. Results Cognitive-behavioral therapy significantly reduced spider phobic symptoms in all patients. Symptom reduction during anticipatory anxiety was accompanied by reduced bilateral CBF in the parahippocampal gyrus, ventral anterior thalamus, Brodmann area 8, and the anterior cingulate cortex. During postprocessing of phobia-relevant stimuli, patients showed reduced CBF in the bilateral insula, components of the motor cortex, and areas associated with language functions. Conclusions Longitudinal CBF dynamics following CBT were in concordance with results from several studies using BOLD fMRI to investigate the effects of psychotherapy on brain activity. CBF can be quantified by ASL, with the principal advantage of sensitivity to slow variations in neural activity and task independence. Therefore, ASL may be a suitable method for monitoring and evaluating the efficacy of psychotherapy or pharmacotherapy approaches

In Need of Psychiatric Help - Leave a Message after the Beep

Background/Aim: Every day, a substantial proportion of the general population experiences the distressing and frightening signs of an upcoming psychiatric illness. The consequences can be enormous because severe psychiatric disorders typically cause the loss of the ability to work and often mean a long-term burden for both the patients and their families. Even though most developed countries have an exceptionally high density of general practitioners and psychiatrists in private practice, getting a mental health appointment and seeing a doctor is often very difficult for patients with acute psychiatric symptoms. This study aimed at quantifying the time delay involved in seeking medical attendance when psychiatric disorders begin to develop. Methods: Two female actors with well-proven experiences of realistically simulating the clinical presentation of depression and psychotic disorders made systematic phone calls to 106 psychiatrists in private practice and 106 general practitioners (GPs) of the Zurich City area. The actors asked for an appointment at the doctor's earliest convenience due to acute psychiatric symptoms. We assessed (1) the number of phone calls it took to reach each doctor; (2) the time it took to book an appointment; (3) the time span between the first phone call and the earliest available appointment, and (4) the possibility of personal contact with a doctor prior to booking the appointment. Results: A total of 383 phone calls were made by the two actors (227 to psychiatrists and 156 to GPs) which resulted in analyzable data from 102 psychiatrist and 106 GP practices. Two thirds (68%) of the phone calls to the psychiatrists in private practice were answered by voice mail, compared to 21% among the GPs. A personal contact was established with 56% of the psychiatrists and 95% of the GPs. On average, 7.3 phone calls were necessary to successfully book an appointment with a psychiatrist. Almost half of the psychiatrists (45.6%) were not accepting new patients so appointments were able to be booked in less than one third of cases (30.4%). The situation was significantly better with GPs (p < 0.002) but depended on clinical diagnosis (p < 0.01). The waiting time to seeing a psychiatrist often far exceeded 7 days. Conclusions: A high density of psychiatrists in private practice does not necessarily improve the long and troublesome circumstances of obtaining a mental health appointment in acute psychiatric situations. Under these circumstances, a considerable proportion of patients might give up prior to seeing a doctor. This has important implications - many patients could miss the potential benefits from timely therapeutic interventions which can significantly modify both the acute and long-term course of the illness. The situation might be improved if psychiatrists and GPs joined forces in the form of group practices or networks as this would readily ensure (1) a rapid mental health triage by assessing and categorizing the urgency of mental health-related problems, and (2) timely therapeutic interventions whenever indicated

Repeated measurements of learned irrelevance by a novel within-subject paradigm in humans

Learned irrelevance (LIrr) refers to the retardation of classical conditioning following preexposure of the to-be-associated stimuli. Healthy volunteers have been tested on three occasions with a new LIrr paradigm avoiding methodological problems which afflict traditional paradigms. A significant LIrr effect was demonstrated on each occasion. Thus, the new paradigm enables repeated measurements of LIrr and might be useful in evaluating long-term effects of medication in psychiatric disorders exhibiting aberrant LIrr