BNA2017 POSTER ABSTRACTS SESSION 3 WEDNESDAY 12TH APRIL Poster number: P-W001 Theme: Attention, motivation, behaviour Do attention and expectation act interactively or additively? - A multisensory perspective Authors: Arianna Zuanazzi, Uta Noppeney - School of Psychology University of Birmingham Attention (i.e. task relevance) and expectation (i.e. stimulus probability) are two critical determinants of perception. While attention is thought to increase the neural response to external stimuli, expectation is considered to attenuate it. Predictive coding models and recent neuroimaging research suggest that attention and expectation shape neural processing in an interactive fashion whereby attention reverses the attenuation for expected signals. Operationally, attention is often manipulated by asking participants to respond only to the ‘attended’ stimuli. Consequently, the synergistic effects of attention and expectation could only be evaluated at the neural level, but not at the behavioural level where ‘unattended’ stimuli are not responded to. This study developed a novel multisensory paradigm that allowed us to evaluate interactive effects of attention and expectation at the behavioural and neural level. In two experiments, we presented participants with auditory and visual signals in their left or right hemifields. We manipulated stimulus frequency or response requirements only to auditory signals, allowing us to measure the multisensory effects of spatial attention and expectation on behavioural responses to visual signals. Importantly, while experiment 1 manipulated expectation directly via the frequency of auditory stimuli as in (1), experiment 2 determined it indirectly via non- target stimuli that are not responded to as in (2). Our results demonstrate that the synergistic behavioural effects of attention and expectation differ across paradigms. While in experiment 1 attention and expectation influence response times interactively, in experiment 2 the two effects determine response times additively. We explain these discrepant results by a combination of overall response probability and response probabilities conditioned on the spatial hemifield where the stimulus was presented, that differ across the two paradigms. Response times reflect response probability determined by the specific manipulation employed. Concurrent fMRI experiments investigate the neural mechanisms underlying these multisensory effects of attention and expectation. (1)Kok et al.(2012) doi.org/10.1093/cercor/bhr310 (2)Jiang et al.(2013) doi.org/10.1523/JNEUROSCI.3308-13.2013 Contact email address: [email protected] Poster number: P-W002 Theme: Attention, motivation, behaviour Trait impulsivity in rats is associated with reduced myoinositol in the infralimbic cortex Authors: Bianca Jupp, Suzanne Lemstra, Bas Van Der Veen, Steve Sawiak, Rebecca Barlow - Psychology Cambridge University, Anton Pekcec - CNS Discovery Support Boehringer Ingelheim, Tom Bretschneider - Drug Discovery Support Boehringer Ingelheim, Janet Nicholson - CNS Discovery Support Boehringer Ingelheim, Trevor Robbins, Jeffrey Dalley - Psychology Cambridge University Impulsivity is defined as a tendency for premature, unduly risky and poorly conceived actions and as a behavioural trait is associated with a number of psychiatric disorders including attention deficit/hyperactivity disorder (ADHD) and bipolar disorder, and is thought to involve dysfunction within cortico-striatal circuitries. Here we investigate the putative metabolic cortico-striatal correlates of impulsivity using in-vivo proton magnetic resonance spectroscopy (1H MRS) in rats selected on the basis of expression of innately high or low levels of premature responding on the five choice serial reaction time task (5CSRTT). High impulsive rats demonstrated significantly reduced prefrontal cortical levels of myoinositol, a metabolite associated with the inositol triphosphate/calcium (IP3/Ca2+) signalling cascade. No other differences in metabolite concentrations were observed between high and low impulsive animals in either the prefrontal cortex or striatum. Ex-vivo mass spectroscopy examining myoinositol levels in individual sub-regions of the prefrontal cortex in an independent group of animals confirmed a reduction in myoinositol levels in high impulsive rats, specifically within the infralimbic cortex. To further investigate the ontology of this metabolic dysfunction, we examined transcript levels of a number of key enzymes and proteins involved in the metabolism and cellular transport of myoinositol and its precursors within the infralimbic cortex. Significant reductions in transcript levels were observed for the enzyme inositol monophosphate synthanse 1 (IMPase1) and the sodium inositol co-transporter (SMIT1) in high impulsive rats compared with low impulsive rats. The main findings of this study suggest that trait impulsivity in rats is associated with reductions in the level of myoinositol in the infralimbic cortex, potentially driven by reductions in the capacity for intracellular transport and calcium signalling. Contact email address: [email protected] BNA2017 POSTER ABSTRACTS SESSION 3 WEDNESDAY 12TH APRIL Poster number: P-W003 Theme: Attention, motivation, behaviour Visual imagery: the experience of aphantasia and hyperphantasia Authors: Crawford Winlove, James Gaddum, Brittany Heuerman-Williamson, Adam Zema - Medical School University of Exeter AIM Imagination - the ability to call to mind things that are not present to the senses - allows us to explore the past, the future, and the potentially possible. For most people, visual imagery is a conspicuous element of imagination, but some people report its absence. We have called this absence of visual imagery aphantasia. Here, we present preliminary data from a large questionnaire survey of individuals whose imagery falls at the extremes of the vividness spectrum. METHOD 2,012 members of our user group completed a Visual Imagery Questionnaire, (VVIQ, Marks 1973), a widely-accepted measure of mental imagery. Participants scoring between 16 and 24 on the VVIQ, were classified as aphantasic; those scoring >77 were classified as hyperphantasic. Their employment was categorised using Standard Occupational Classification (US Department of Labor, 2000). RESULTS We focus here on individuals with lifelong aphantasia or hyperphantasia who comprised the overwhelming majority of participants. 19% of people with aphantasia worked in computer and mathematical occupations; only 8% of people with hyperphantasia reported working in these fields. Amongst those with vivid imagery, 29% worked in the Arts, Design, Entertainment, Sports, and Media Occupations, compared to 13% of people with aphantasia. A family history in first degree relatives of aphantasia and hyperphantasia was obtained in 15-20% of participants. The majority of participants with aphantasia (70%) experience imagery in dreams. Roughly equal numbers of participants with aphantasia reported the presence and absence of imagery in other modalities. Face recognition difficulties were reported commonly by participants with aphantasia (35%). More individuals with aphantasia (34%) than hyperphantasia (5%) regarded their autobiographical memory as poor; conversely 23% of people with hyperphantasia compared to 8% of people with aphantasia regarded their autobiographical memory as good. CONCLUSIONS Preliminary data from this large sample of individuals falling at the extremes of the imagery spectrum suggests that imagery vividness is a lifelong trait. Low imagery vividness appears to be overrepresented among people working in IT related and mathematical domains, high vividness among those working in Contact email address: [email protected] Poster number: P-W004 Theme: Attention, motivation, behaviour Categorical differences in the conscious access to visual objects Authors: Daniel Lindh - School of psychology University of Birmingham The ability to consciously recognise visual objects is crucial for adaptive behaviour and survival. Conscious access to visual objects has been studied using the Attentional Blink (AB), where two targets (T1 and T2) are embedded with visual masks in a rapid serial visual presentation (RSVP). In the AB, the ability to detect T2 is reduced when presented 200-500ms post T1. Research using functional Magnetic Resonance Imaging (fMRI) has proven useful to identify the underlying brain mechanisms of conscious access. Given the challenges inherent to the limited temporal resolution of fMRI, researchers have designed AB-studies in which T1 and T2 targets are selected from image categories known to engage different regions in the visual stream. However, to integrate these findings into a consistent model of conscious access, the variability in detection thresholds across categories needs to be assessed. Specifically, we investigated the categorical differences in conscious and unconscious processing using a behavioural attentional blink task. Here, we presented participants with 48 pictures of objects from eight categories (fruits and vegetables, processed foods, objects, scenes, animal bodies, animal faces, human bodies, and human faces) in an AB-task (Fig. 1A). Each picture was presented as T1, and at two different T2-lags (200ms and 700ms post T1). To compare the performance at recalling target objects across categories, we used a factorial ANOVA with performance effect of T2-lag and object category as factors (Fig. 1B). We observed main effects of T2-lag (F(1,20)=51.47, p < 0.001) and category
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