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Telencephalic and preoptic areas integrate sexual behavior in hime salmon (landlocked red salmon, Oncorhynchus nerka): results of electrical brain stimulation experiments.
Various patterns of sexual behavior were evoked in freely swimming hime salmon by electrical stimulation of specific loci in the telencephalon and the preoptic area (POA) using chronically implanted electrodes. Furthermore, co-ordinated sexual behavior corresponding to stages of the natural spawning sequence was elicited from some of these brain regions. These results suggest that (1) sexual behavior is integrated in specific parts of the telencephalon and POA, and (2) within these regions there is a hierarchy of neural systems which mediate progressively more complete components of normal sexual behavior.
Focused Representation of Successive Task Episodes in Frontal and Parietal Cortex.
Complex cognition is dynamic, with each stage of a task requiring new cognitive processes appropriately linked to stimulus or other content. To investigate control over successive task stages, we recorded neural activity in lateral frontal and parietal cortex as monkeys carried out a complex object selection task, with each trial separated into phases of visual selection and learning from feedback. To study capacity limitation, complexity was manipulated by varying the number of object targets to be learned in each problem. Different task phases were associated with quasi-independent patterns of activity and information coding, with no suggestion of sustained activity linked to a current target. Object and location coding were largely parallel in frontal and inferior parietal cortex, though frontal cortex showed somewhat stronger object representation at feedback, and more sustained location coding at choice. At both feedback and choice, coding precision diminished as task complexity increased, matching a decline in performance. We suggest that, across successive task steps, there is radical but capacity-limited reorganization of frontoparietal activity, selecting different cognitive operations linked to their current targets.
A One-Shot Shift from Explore to Exploit in Monkey Prefrontal Cortex.
Much animal learning is slow, with cumulative changes in behavior driven by reward prediction errors. When the abstract structure of a problem is known, however, both animals and formal learning models can rapidly attach new items to their roles within this structure, sometimes in a single trial. Frontal cortex is likely to play a key role in this process. To examine information seeking and use in a known problem structure, we trained monkeys in an explore/exploit task, requiring the animal first to test objects for their association with reward, then, once rewarded objects were found, to reselect them on further trials for further rewards. Many cells in the frontal cortex showed an explore/exploit preference aligned with one-shot learning in the monkeys' behavior: the population switched from an explore state to an exploit state after a single trial of learning but partially maintained the explore state if an error indicated that learning had failed. Binary switch from explore to exploit was not explained by continuous changes linked to expectancy or prediction error. Explore/exploit preferences were independent for two stages of the trial: object selection and receipt of feedback. Within an established task structure, frontal activity may control the separate processes of explore and exploit, switching in one trial between the two.SIGNIFICANCE STATEMENT Much animal learning is slow, with cumulative changes in behavior driven by reward prediction errors. When the abstract structure a problem is known, however, both animals and formal learning models can rapidly attach new items to their roles within this structure. To address transitions in neural activity during one-shot learning, we trained monkeys in an explore/exploit task using familiar objects and a highly familiar task structure. When learning was rapid, many frontal neurons showed a binary, one-shot switch between explore and exploit. Within an established task structure, frontal activity may control the separate operations of exploring alternative objects to establish their current role, then exploiting this knowledge for further reward.
Like a Punch in the Gut: A Novel Perspective On Annual Recurrences of Ulcerative Colitis.
BACKGROUND: Ulcerative colitis (UC), a chronic inflammatory bowel disease, causes stomach pain, diarrhea, and rectal bleeding. The exact cause is unknown, but it is thought to involve genetic, environmental, and psychological factors. Some people experience annual flare-ups without obvious reason. This article adopts a theory-driven approach to consider how and why past traumatic events may contribute to annual flare-ups. METHODS: We applied learning theory, which explains the development of re-experiencing phenomena in post-traumatic stress disorder (PTSD), to better understand the occurrence of annual flares in patients living with UC. RESULTS: Two possibilities emerged in which associative learning may contribute to annual UC flares. First, flare-ups could be a physical response to sensory cues in the present that overlap with trauma experienced at the first onset of UC. Annual episodes may strengthen the UC flare as a learned physiological response to trauma reminders. Second, flare-ups may result from elevated stress due to trauma re-experiencing at anniversaries. Sensory features of the initial UC trauma may be associated with strong reactions, which generalize to similar stimuli, triggering re-experiencing symptoms and increasing psychological stress. Elevated stress raises glucocorticoid levels, promoting UC-specific inflammation. Stimulus discrimination from cognitive therapy for PTSD may help to over-ride the associations that have formed between sensory features of past trauma, linked reactions, and similar cues in the present. CONCLUSIONS: Research is needed to understand how traumatic events influence the onset and recurrence of ulcerative colitis, as well as the potential benefits of stimulus discrimination for reducing the frequency of annual flares.
The Oxford Paranoia Defence Behaviours Questionnaire (O-PDQ): assessing paranoia-related safety-seeking behaviours.
BACKGROUND: Defence behaviours - actions carried out to reduce perceived threat - are an important maintenance factor for persecutory delusions. Avoidance of feared situations and subtle in-situation behaviours reduce opportunities for new learning and are erroneously credited for the non-occurrence of harm; hence inaccurate fears are maintained. In contrast, exposure to feared situations whilst dropping defence behaviours - a key technique of cognitive therapy for paranoia - allows the discovery of new information concerning safety, thereby reducing persecutory delusions. AIM: We aimed to develop for use in research and clinical practice a self-report assessment of paranoia-related defence behaviours. METHOD: A 64-item pool was developed from interviews with 106 patients with persecutory delusions, and completed by 53 patients with persecutory delusions, 592 people with elevated paranoia, and 2108 people with low paranoia. Exploratory and confirmatory factor analyses were used to derive the measure. Reliability and validity were assessed. RESULTS: Two scales were developed: a 12-item avoidance scale and a 20-item in-situation defences scale. The avoidance scale had three factors (indoor spaces, outdoor spaces, and interactions) with an excellent model fit (CFI=0.98, TLI=0.97, RMSEA=0.04, SRMR=0.027). The in-situation defences scale had a 5-factor model (maintaining safety at home, mitigating risk, staying vigilant, preparing for escape, and keeping a low profile) with a good fit (CFI=0.95, TLI=0.94, RMSEA=0.046, SRMR=0.039). Both scales demonstrated good internal reliability, test-retest reliability, and construct validity. CONCLUSIONS: The Oxford Paranoia Defence Behaviours Questionnaire is a psychometrically robust scale that can assess a key factor in the maintenance of persecutory delusions.
Disentangling frontal-striatal contributions to exploration
In this issue of Neuron, Treuting et al.1 present a dissociation between the way anterior cingulate cortex (ACC) and striatum use prediction errors to shape exploration in complementary ways, with ACC tracking prediction errors to reduce uncertainty regarding available choices and striatum using prediction errors to amplify value estimates
Parent–child similarity on autism and ADHD traits and children's social functioning and psychological well-being at 3 years
Background: There is a pressing need for research on neurodevelopmental conditions to focus on predictors of resilient or positive outcomes, rather than core symptoms and impairment. One promising avenue is to consider whether child–parent similarity contributes to a protective family environment. For instance, investigations of the similarity–fit hypothesis have shown that parent–child attention-deficit/hyperactivity disorder (ADHD) trait similarity is associated with more favourable parent or child ratings of parenting and parent–child interaction. However, very little similarity–fit research has focused on autism, and none to date has investigated whether parent–child trait similarity is more broadly predictive of children's outcomes beyond parent–child interaction. We assessed whether parent–child autism and ADHD trait similarity predicted children's social functioning and psychological well-being in early childhood in a family history cohort. Methods: Our analytic sample comprised 222 children (45.5% female) and their parents from a longitudinal family history (autism and/or ADHD) cohort. A novel parent–child trait similarity measure was computed for autism and ADHD traits in each parent–child pair, and robust hierarchical regression was used to assess whether mother–child and father–child autism and ADHD similarity predicted children's social functioning and psychological well-being at age 3 years, after accounting for the main effects of parent and child traits. Results: Mother–child autism trait similarity positively predicted both social functioning and psychological well-being in children, while mother–child ADHD trait similarity positively predicted children's social functioning (but not well-being). Furthermore, father–child autism trait similarity positively predicted children's social functioning, though it fell just short of statistical significance in outlier-robust regression. Conclusions: Our findings suggest that parent–child neurodevelopmental trait similarity may act as a protective or promotive factor for children's early social functioning and psychological well-being. Further work is warranted to determine whether there are similar effects in later childhood and to investigate the potential mechanisms underlying similarity–fit effects on children's outcomes.
Coach-Supported Internet-Based Cognitive Therapy for Social Anxiety Disorder in Hong Kong: Development, Training, and Pilot Clinical Outcomes.
Internet-based Cognitive Therapy for Social Anxiety Disorder (iCT-SAD), a treatment that is normally supported by therapists, has been modified for delivery by trained coaches without mental health practitioner qualifications and has shown promising efficacy for patients in Hong Kong.
Validation of the Coffee Knowledge Test for Assessing Expertise in Coffee
Perception and appreciation of food and beverages are shaped by an individual's knowledge and expertise. While wine expertise has been widely studied, less is known about how coffee expertise influences sensory perception. This study aimed to validate the Coffee Knowledge Test developed by Croijmans and Majid (2016) as a tool for assessing coffee expertise. We adapted the test and examined its reliability using data from 267 participants, comparing novice consumers and coffee professionals. Internal consistency was evaluated using item variability, correlation analysis, and Cronbach's α, while external validity was assessed by comparing scores between the two groups. The test showed sufficient item variability, appropriate correlations, and strong internal consistency. Importantly, coffee professionals scored significantly higher than novices. These results support the Coffee Knowledge Test as a valid and reliable instrument for measuring coffee-related knowledge and expertise.
Real-world waitlist randomised controlled trial of gameChange VR to treat severe agoraphobic avoidance in patients with psychosis: a study protocol.
INTRODUCTION: Many people with psychosis find the world very frightening. It can be difficult for them to do everyday things-for example, walking down a busy street, travelling on a bus or going to the shops. Sometimes, the fears are so great that individuals rarely leave their homes. gameChange virtual reality therapy is designed to reduce this agoraphobic avoidance. In gameChange, users practise going into computerised immersive versions of ordinary situations. A virtual therapist guides users through the programme. A mental health worker also supports people. People normally do six sessions of gameChange, but now they can do more as headsets can be left with many people. We originally tested gameChange with 346 patients with psychosis. People saw a significant reduction in their fears. People with the most severe problems made the biggest improvements. This led to gameChange receiving National Institute for Health and Care Excellence (NICE) Early Value Assessment (EVA) approval for its use with patients with psychosis who have severe agoraphobic avoidance. NICE EVA approval is conditional on further evidence generation. We aim to carry out a real-world trial of gameChange used in the NHS. The overall aim is to gather evidence on the four essential areas (clinical benefits on agoraphobia, level of engagement and adherence, healthcare resource use, adverse effects) and the two further supporting areas (health-related quality of life, generalisability) identified in the NICE evidence generation plan for gameChange. METHODS AND ANALYSIS: 200 patients with psychosis and severe agoraphobic avoidance will be randomised (1:1) to receive gameChange in addition to treatment as usual (TAU) or to a waitlist control group receiving TAU. Assessments will be conducted blind to group allocation at baseline, 8 weeks (end of treatment) and 26 weeks (follow-up). The trial will be embedded in services in at least seven National Health Service (NHS) trusts across England. The primary outcome is agoraphobic avoidance at 26 weeks assessed with the Oxford Agoraphobic Avoidance Scale. The secondary clinical outcomes are agoraphobic distress, paranoia and social contacts. There will be tests of moderation of the main clinical outcome. Treatment acceptability, adverse effects and cost-effectiveness will also be assessed. The target estimand is the treatment policy estimand and all primary and secondary analyses will be carried out incorporating data from all participants including those who do not complete treatment. ETHICS AND DISSEMINATION: The trial has received ethical approval from the NHS Health Research Authority and Health and Care Research Wales (25/WA/0081). A key output will be the evidence needed for a NICE guidance update on gameChange and a clear recommendation concerning future routine use in the NHS. TRIAL REGISTRATION NUMBER: ISRCTN79060696.
Apathy and impulsivity in neurological and psychiatric disorders
Apathy and impulsivity are debilitating syndromes of motivation that are common across neurological and psychiatric disorders. Both are associated with pathology within well described fronto-striatal networks where dopaminergic neurons play an important role in regulating motivated behavior. In this chapter, we investigate whether dopaminergic dysfunction within this network is associated with either apathetic or impulsive behavior. We focus on patients with Parkinson's disease and schizophrenia, investigating a wide range of behavioral and neuroimaging studies. Current findings suggest that both apathy and impulsivity are associated with altered responsiveness to rewards during decision-making and altered function within fronto-striatal networks. While dopaminergic therapy also alters reward sensitivity, there are instances where the effects of apathy and/or impulsivity on this metric are independent of—and extend beyond—dopaminergic tone. This suggests a more nuanced relationship between fronto-striatal dopamine and human motivation syndromes that warrants further investigation.