Differential Effects of Single-Dose Escitalopram on Cognitive and Affective Interference during Stroop Task

Background and objective: Our aim was to study the regulatory role of serotonin [(5-hydroxytryptamine (5-HT)] on two key nodes in the cognitive control networks – the anterior cingulate cortex (ACC) and the dorsolateral prefrontal cortex (DLPFC). We hypothesized that increasing the levels of 5-HT would preferentially modulate the activity in ACC during cognitive control during interference by negative affects compared to cognitive control during interference by a superimposed cognitive task. Methods: We performed a functional magnetic resonance imaging investigation on 11 healthy individuals, comparing the effects of the selective 5-HT reuptake inhibitor escitalopram on brain oxygenation level dependent signals in the ACC and the DLPFC using affective and cognitive counting Stroop paradigms (aStroop and cStroop). Results: Escitalopram significantly decreased the activity in rostral ACC during aStroop compared to cStroop (p < 0.05). In the absence of escitalopram, both aStroop and cStroop significantly activated ACC and DLPFC (Z ≥ 2.3, p < 0.05). Conclusion: We conclude that escitalopram in a region and task specific manner modified the cognitive control networks and preferentially decreased activity induced by affective interference in the ACC

Role of the cholinergic system in the psychopathology and treatment of schizophrenia: a protocol for a scoping review

Introduction and objectiveThe cholinergic system has broad implications for affective and cognitive processes, which makes it pertinent for the psychopathology and treatment of mental disorders. Questions concerning its role in schizophrenia, a chronic disorder characterized by psychosis, emotional blunting and cognitive deficits, have been made particularly relevant due to the recent Food and Drug Administration (FDA) approval of a muscarinic agonist as an antipsychotic agent. The present paper details the protocol for a scoping review that will map models, evidence and research gaps concerning the role of the cholinergic system in the positive, negative and cognitive domains implicated in the psychopathology of schizophrenia.Methods and analysisThe scoping review will be conducted according to JBI (formerly the Joanna Briggs institute) methodology, using articles from the following databases: PubMed, Embase, Scopus, Cochrane Central Register of Controlled Trials and PsycInfo. Two independent reviewers will screen the articles using title and abstract, after which full text-analysis will determine inclusion. Only published original peer-reviewed English-language studies from the last 20 years that pertain to the review objective will be included. Clinical studies will be assessed for methodological quality and risk of bias. The results, which the reviewers will extract independently of each other using a data extraction tool, will be presented in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analysis Protocol Extension for Scoping Reviews (PRISMA-ScR).DiscussionClarifying the research gaps in the field can indicate where future pre-clinical and clinical studies and systematic reviews can be worthwhile, and the risk of bias assessment aids in this by stratifying the included clinical trials according to quality. However, the language and publication date restrictions risk excluding relevant studies, which can introduce bias

A Synaptic Mechanism for Temporal Filtering of Visual Signals

The visual system transmits information about fast and slow changes in light intensity through separate neural pathways. We used in vivo imaging to investigate how bipolar cells transmit these signals to the inner retina. We found that the volume of the synaptic terminal is an intrinsic property that contributes to different temporal filters. Individual cells transmit through multiple terminals varying in size, but smaller terminals generate faster and larger calcium transients to trigger vesicle release with higher initial gain, followed by more profound adaptation. Smaller terminals transmitted higher stimulus frequencies more effectively. Modeling global calcium dynamics triggering vesicle release indicated that variations in the volume of presynaptic compartments contribute directly to all these differences in response dynamics. These results indicate how one neuron can transmit different temporal components in the visual signal through synaptic terminals of varying geometries with different adaptational properties

“InMotion”—Mixed physical exercise program with creative movement as an intervention for adults with schizophrenia: study protocol for a randomized controlled trial

BackgroundSchizophrenia is among the world’s top 10 causes of long-term disability with symptoms that lead to major problems in social and occupational functioning, and in self-care. Therefore, it is important to investigate the efficacy of complementary treatment options for conventionally used antipsychotic medication, such as physical training, and psychosocial interventions.ObjectiveTo combine aerobic and strength training with cognitive, emotional and social stimulation in one intervention for people with schizophrenia and test the feasibility and effects of this intervention.MethodsThe study is a mixed-method randomized controlled trial to evaluate the effects of a 12-week intervention for adults with schizophrenia. The treatment group (30 participants) will receive the intervention in addition to standard care and the control group (30 participants) only standard care. The intervention consists of 24 biweekly sessions with a duration of 60 min. The pre-test (weeks from 4 to 2 prior to the intervention) and post-test (week 12) include clinical measure (PANSS), quality of life, social performance, movement quantity, brain function and eye tracking measures. In addition, a treatment subgroup of 12–15 participants and their family member or other next of kin will complete a qualitative interview as a part of their post-test. Two follow-up tests, including clinical, quality of life, brain function and eye tracking will be made at 6 and 12 months from the completion of the intervention to both study groups. The primary outcome is change in negative symptoms. Secondary outcome measures include general and positive symptoms, quality of life, social performance, movement quantity, brain function and eye tracking. Explorative outcome includes patient and family member or other next of kin interview.ResultsPilot data was collected by June 2023 and the main data collection will begin in September 2023. The final follow-up is anticipated to be completed by 2026.ConclusionThe InMotion study will provide new knowledge on the feasibility, efficacy, and experiences of a novel intervention for adults with schizophrenia. The hypothesis is that regular participation in the intervention will reduce clinical symptoms, normalize physiological measures such as brain activation, and contribute to new active habits for the participants.Trial registrationClinicalTrials.gov, identifier NCT05673941

Paired pulse analysis of ATP and noradrenaline release from sympathetic nerves of rat tail artery and mouse vas deferens: effects of K(+) channel blockers

1. The paired pulse stimulus paradigm – two pulses of equal strength delivered at variable interpulse intervals – was used to study the release of ATP and noradrenaline (NA) from post ganglionic sympathetic nerves of rat tail artery and mouse vas deferens. 2. Excitatory junction currents (EJCs) were used to measure the release of ATP, and differential pulse amperometry to measure that of NA. 3. At interpulse intervals of 0.1–1 s paired pulse stimulation caused an increase in the size of the second EJC, both in rat tail artery and mouse vas deferens. As the interpulse interval was increased to 10 s or more, the two EJCs became of equal size. 4. In both preparations the K(+) channel blockers tetraethylammonium (TEA, 20 mM) and 4-aminopyridine (4-AP, 1 mM) prolonged the duration of the nerve terminal spike and greatly amplified the first EJC of the pair. 5. In the presence of TEA and 4-AP in rat tail artery paired pulse stimulation caused a dramatic depression of the second EJC without markedly affecting the nerve terminal spike. The depression of the second EJC decreased with increasing interpulse intervals, and also when external Ca(2+) was reduced to 0.2 mM. In mouse vas deferens, TEA and 4-AP caused only a modest depression of the second EJC. 6. In rat tail artery in the presence of TEA and 4-AP paired pulse stimulation caused a depression of the NA oxidation current evoked by the second pulse, which was similar in magnitude and time course to that of the EJC. Similar TEA and 4-AP induced depression of the second pulse response was also observed when the purinergic and noradrenergic components of the contractile response were investigated. 7. The results show that in rat tail artery K(+) channel blockers cause a dramatic paired pulse depression of the release of ATP and NA. The similarity in the depression of the EJC, the NA oxidation current, and the purinergic and noradrenergic components of the contractile response is compatible with the hypothesis that ATP and NA are released in parallel from the same neuronal sources