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RELIGION AND THE SUSCEPTIBILITY TO FALSE BELIEFS
Religion has played a particularly important role in human evolution. It is the one trait that categorically distinguishes us from other animals. Yet it is about belief in a world that does not exist - the spirit world. I shall argue that it arises through two very ancient psychological predispositions. A tendency for the magical to have priority when we cannot see an obvious explanation and a strong tendency to be attracted to charismatic leaders. The first is a derivative of our advanced mentalising capacities, which allow us to imagine worlds that do not exist. The second is seems to be associated with the fact that networks that evolve leaders work more efficiently. Both of these played a central role in our evolution as a species.
Target selection signals causally influence human perceptual decision making.
The ability to form decisions is a foundational cognitive function which is impaired across many psychiatric and neurological conditions. Understanding the neural processes underpinning clinical deficits may provide insights into the fundamental mechanisms of decision making. The N2c has been identified as an EEG signal indexing the efficiency of early target selection, which subsequently influences the timing of perceptual reports through modulating neural evidence accumulation rates. Evidence for the contribution of the N2c to human decision making however has thus far come from correlational research in neurologically healthy individuals. Here, we capitalised on the superior temporal resolution of EEG to show that unilateral brain lesions in male and female humans were associated with specific deficits in both the timing and strength of the N2c in the damaged hemisphere, with corresponding deficits in the timing of perceptual reports contralaterally. The extent to which the N2c influenced clinical deficits in perceptual reporting speed depended on neural rates of evidence accumulation. This work provides causal evidence that the N2c indexes an early, hemisphere-specific process supporting human decision making. This non-invasive EEG marker could be used to monitor novel approaches for remediating clinical deficits in perceptual decision making across a range of brain disorders.Significance Statement Understanding how particular brain processes contribute to decision-making is crucial for our treatment of psychiatric and neurological disorders. This study provides causal evidence linking deficits in speed of visual processing to specific well-delineated EEG signals representing early target selection and evidence accumulation, in individuals with brain lesions. By showing how these lesions disrupt perceptual decisions, this work identifies a potential biomarker for decision-making deficits. This EEG measure offers a promising, non-invasive tool to track and refine treatments aimed at restoring decision-making abilities in affected patients.
Contributed Talks I: The role of fixational drift in the Vernier task.
We develop a simple one-dimensional continuum model of the Vernier discrimination task to study the impact of Gaussian blur, fixational drift, receptor noise, and retinal adaptation on an ideal observer's Vernier performance. Two rectangular stimuli with a prescribed width and relative offset are subjected to a Gaussian blur. Fixational drift shifts the resulting signal with time. The perceived signal is the weighted average over the history of local stimulation encoded by an adaptation kernel. We model this kernel as a difference of two exponentials, introducing two timescales describing initial integration and eventual recovery of a receptor. Ultimately, Gaussian white noise is added to capture random receptor fluctuations. Based on the Bayesian estimation of location and relative offset of both stimuli, we can study Vernier performance through numerical simulation as well as through analytical approximation for different eye movements. Analyzing diffusive motion in particular, we extract the diffusion constant that optimizes stimulus localization for long observation times. This optimal diffusion constant is inversely proportional to an average of the two timescales describing adaptation and proportional to the square of the larger of stimulus size or blurring width, giving rise to two separate regimes. We generalize our analysis to optimize discrimination and extend the class of eye motions considered beyond purely diffusive drift, e.g. with the inclusion of persistence.
Age-invariant benefits of spatiotemporal predictions amidst distraction during dynamic visual search.
Visual search tasks are widely used to study attention amidst distraction, often revealing age-related differences. Research shows older adults typically exhibit poorer performance and greater sensitivity to distraction, reflecting declines in goal-driven attention. However, traditional search tasks are static and fail to capture the challenges and opportunities in natural environments, which include predictive structures within extended contexts. We designed a search variation where targets and distractors compete over time and embedded spatiotemporal regularities afford prediction-led guidance of attention. Critically, we manipulated the number of distractors to chart how benefits of expectations and deficits from distraction varied with age. Younger and older adults searched for multiple targets as they faded in and out of the display while varying the number of distracting elements between trials. Half the targets appeared at the same time and approximate locations and could be predicted. While we found evidence for decrement and elevated sensitivity to distraction with increasing age, benefits from predictions occurred in all groups. Interestingly, regardless of age, effects of predictions were only significant during periods of high distraction. This work extends our understanding of attention control through ageing to dynamic settings and indicates a dissociation between goal-directed and learning-driven attentional guidance.
Young people's attitudes towards online self-help single-session interventions: findings from a co-produced qualitative study.
BACKGROUND: Many young people experience at least subthreshold depression symptoms which impact their functioning. Yet, access to evidence-based help is limited, with barriers such as service thresholds, stigma, and lack of knowledge about mental health and available services. One way to ensure young people have access to free, early, immediate and anonymous help is through online self-help single-session interventions. This study aimed to qualitatively explore young people's perceptions of and attitudes towards these interventions. METHODS: Twenty-four young people (UK based, age 15-18) took part in qualitative semi-structured interviews which were hosted online and co-conducted with a young research team (N = 4, age 16-18), during which we described online single-session interventions and asked participants for their perspectives. Together with our young researchers, we analyzed the data using reflexive thematic analysis. RESULTS: Three themes were generated: (1) Will it help, or won't it? Hope versus skepticism; (2) Why this approach? Benefits of single-session interventions for young people; and (3) Have you considered this? Logistics for implementation. CONCLUSIONS: The current study highlights that whilst young people perceived there to be many benefits associated with online single-session interventions, including anonymity, easy access, and lack of disclosure, they expressed doubts regarding sufficiency and ability to address severe mental health problems. Despite this, the potentially preventative effects during the early stages of help-seeking were highlighted, alongside single-session interventions acting as a gateway to further help-seeking and support. However, logistical considerations should also be reflected upon when developing online single-session interventions, including where they are advertised, age appropriateness, and how to demonstrate trustworthiness.
Smelling x as y? On (the impossibility of) multistable perception in the chemical senses.
Multistable percepts are intriguing phenomena whereby an ambiguous sensory input can be perceived in one of several qualitatively different ways. In such cases, people can switch their attention to perceive the stimulus in either way, though they typically cannot maintain both interpretations in awareness simultaneously. The abundance of evidence demonstrating multistable perception in the visual and auditory modalities can be contrasted with the scarcity, if not absence, of studies reporting similar phenomena in the chemical senses (primarily olfaction and gustation), prompting an intriguing question about this apparent qualitative difference between the senses. This paper seeks to address this question by first briefly reviewing multistable perceptual phenomena in vision and audition to underscore their defining features. We then assess the limited body of research that has occasionally linked multistability to the chemical senses. While a few studies suggest loose analogies between olfactory perception and visual or auditory multistability, no compelling evidence exists for such phenomena in taste. We argue that this absence is unlikely to be explained by any single factor. Rather, it appears to stem from a confluence of constraints, including the lack of spatio-temporal structure and intrinsic dimensionality in chemosensory stimuli, as well as their distinct evolutionary functions and cognitive framing. Together, these factors may help to explain why multistable perceptual experiences seem not to emerge in the chemical senses.
Mapping the Dynamics of Generalized Anxiety Symptoms and Actionable Transdiagnostic Mechanisms: A Panel Study
Background: The long‐term dynamic interaction between symptoms of generalized anxiety disorder (GAD) and their theorized mechanistic processes derived from three treatment models of GAD—the emotion dysregulation model, the model underlying metacognitive therapy (MCT), and the intolerance of uncertainty model—was investigated.Methods: Four data waves 2 months apart were delivered by a representative population sample of 4361 participants during the COVID‐19 pandemic in Norway. Networks were estimated using the newly developed panel graphical vector autoregression (panel‐GVAR) methods.Results: In the temporal network, and consistent with processes stipulated in the metacognitive model, the experience that worry is uncontrollable predicted the GAD symptom fear of awful events, which in turn predicted a range of other GAD symptoms, that is, anxiety, restlessness, and irritability. Fear of awful events had high outstrength, that is, predicted other variables to a large degree. Inconsistent with the metacognitive model, the coping strategy thought suppression negatively predicted restlessness. Consistent with the emotion dysregulation model, emotion dysregulation predicted avoidance. No relationships proposed by the intolerance of uncertainty model of GAD were identified in the temporal network. The contemporaneous network was dense with nodes clustering according to the constructs they belonged to.Conclusions: The findings indicate the importance of the theory‐derived variables, the experience and belief that worry is uncontrollable and emotion dysregulation, as potential targets for intervention to alleviate GAD symptoms. The findings also indicate that uncontrollability of worry and fear of awful events should be considered central symptoms of GAD in a within‐individual diagnostics supplementary to current diagnostic manuals, such as the Diagnostic and Statistical Manual of Mental Disorders 5th edition (DSM‐5).
Poster Session: Characteristic differences in eye movements in people with Parkinson's disease.
Parkinson's disease is a neurodegenerative condition that impairs motor control, including oculomotor function. This study focuses on identifying characteristic differences in eye movements between people with Parkinson's diseases and healthy controls across four different tasks. Two static tasks, a fixation task and a tumbling E task, were measured using an adaptive optics scanning laser ophthalmoscope (AOSLO) to capture fixational eye movements with high spatial and temporal resolution. Two moving target tasks, guided saccade and smooth pursuit, were measured using the EyeLink 1000 Plus to study large-scale eye movements. Three participants with Parkinson's disease and three healthy control performed these tasks. In the fixation task, the participant fixated on a static target for 5s, and in the tumbling E task, an 'E' near the acuity limit was presented in different orientations for 0.7s. The guided saccade task required the participant to quickly shift their gaze between locations separated by 11ᵒ, while the smooth pursuit task involved tracking a smoothly moving target at two different speeds: 10ᵒ/s and 20ᵒ/s. Both moving target tasks were performed in horizontal and vertical directions. Oculomotor parameters such as saccade amplitude, saccade velocity, saccadic delay, saccadic rate, and intersaccadic intervals were extracted from the eye movement trace. Here we report the differences in these parameters between healthy controls and participants with Parkinson's disease.
Working memory filtering at encoding and maintenance in healthy ageing, Alzheimer's and Parkinson's disease.
The differential impact on working memory (WM) performance of distractors presented at encoding or during maintenance was investigated in Alzheimer's Disease (AD), Parkinson's Disease (PD) patients, elderly (EHC) and young healthy controls (YHC), (n = 28 per group). Participants reported the orientation of an arrow from a set of either two or three items, with a distractor present either at encoding or at maintenance. MRI data with hippocampal volumes was also acquired. Mean absolute error and mixture model metrics i.e., memory precision, target detection, misbinding (swapping the features of an object with another probed item) and guessing were computed. EHC and PD patients showed good filtering abilities both at encoding and maintenance. However, AD patients exhibited significant filtering deficits specifically when the distractor appeared during maintenance. In healthy ageing there was a prominent decline in WM memory precision, whilst in AD lower target detection and higher guessing were the main sources of error. Conversely, PD was associated only with higher guessing rates. Hippocampal volume was significantly correlated with filtering during maintenance - but not at encoding. These findings demonstrate how healthy ageing and neurodegenerative diseases exhibit distinct patterns of WM impairment, including when filtering irrelevant material either at encoding and maintenance.
Framework for understanding movement and physical activity in patients diagnosed with psychosis.
BACKGROUND: Patients diagnosed with psychosis often spend less time than others engaged in exercise and more time sitting down, which likely contributes to poorer physical and mental health. OBJECTIVE: The aim of this study was to develop a comprehensive framework from the perspective of patients, carers, and staff for understanding what promotes movement and physical activity. METHODS: A critical realist approach was taken to design the study. Interviews (n=23) and focus groups (n=12) were conducted with (1) outpatients aged 16 years or older diagnosed with psychosis, and under the care of a mental health team, (2) carers and (3) mental health staff working in the community. Purposive sampling was used to maximise variation in participant characteristics. Data were analysed using reflexive thematic analysis. FINDINGS: 19 patients (9 women and 10 men, mean age=45·0 (SD=12·2) years, 15 White British, 2 Black African, 1 Pakistani and 1 other ethnic group), 14 carers (11 women and 3 men, mean age=59·9 (SD=12·7) years, 13 White British and 1 Asian) and 18 staff (14 women and 4 men, mean age=38·7 (SD=12·3) years, 15 White British, 1 White other, 1 Asian Bangladeshi and 1 other Asian) participated in the study. Five factors were found to promote movement and physical activity. Patients must be able to find a purpose to moving which is meaningful to them (Factor 1: Purpose). Patients need to have an expectation of the positive consequences of movement and physical activity, which can be influenced by others' expectations (Factor 2: Predictions). A patient's current physical (eg, pain) and emotional state (eg, distress about voices) needs to be addressed to allow movement and physical activity (Factor 3: Present state). Movement and physical activity can also be encouraged by the availability of effective and tailored support, provided by engaged and supported people (Factor 4: Provision). Finally, through the identification and interruption of vicious cycles (eg, between inactivity and mood states) more positive cycles can be put in place (Factor 5: Process). CONCLUSIONS AND CLINICAL IMPLICATIONS: The 5 P (Purpose, Predictions, Present state, Provision and Process Physical Activity Framework) for understanding movement and physical activity for people diagnosed with psychosis has the potential to inform future research and guide interventions. A checklist is provided for clinicians to help foster change in activity levels.