Poster Session A 1-41

Saturday, March 6^th, 2021, 4:00 – 6:00 pm in the Exhibit Hall

A1 – Electrophysiological evidence of attention to music in unresponsive hospice patients at the end of life

Presenter

Lawrence Ward

University of British Columbia

Co-Author

Elizabeth Blundon

University of Miami

Co-Author

Romayne Gallagher

University of British Columbia

Co-Author

Lauren Dimaio

Texas Women’s University

The objective of this study was to characterize electrophysiological activity associated with listening to music in a small group of unresponsive hospice patients at the end of life. Young, healthy controls were asked to attend to (Active condition) and ignore (Passive condition) brief (~7s) musical excerpts. A small group of hospice patients were asked to attend to the same musical excerpts (Active condition only), both when they were responsive and again when they became unresponsive. Most (84%) controls showed sustained (~3s) posterio-parietal alpha suppression when they were asked to attend to the music, while far fewer (37%) generated the same response when asked to ignore the music. Similarly, 75% of responsive hospice patients, and 100% of unresponsive hospice patients showed sustained (again, ~3s) posterio-parietal alpha suppression when asked to attend to the music. These results suggest that some unresponsive patients at the end of life may be able to listen to music, despite being unable overtly to indicate their awareness. Music-listening may be a more promising way to engage unresponsive patients compared to neutral stimulation.

Keyword: ATTENTION: Auditory

A2 – Arousal compensates for age-related deficits in early visual attentional selectivity under high attentional load

Presenter

Ringo Huang

University of California, Los Angeles

Co-Author

Kelly Durbin

University of Southern California

Co-Author

David Clewett

University of California, Los Angeles

Co-Author

Martin Dahl

Max Planck Institute for Human Development

Co-Author

Mara Mather

University of Southern California

Increasing task-focused attentional load can enhance distractor suppression in younger adults. Here, we conducted a concurrent eye-tracking and functional magnetic resonance imaging (fMRI) study in younger and older adults to examine whether attentional load can also enhance distractor suppression in older adults, who often have greater difficulty with inhibitory control. In the MRI scanner, participants performed a foveal target detection task while task-irrelevant checkerboards flickered in the periphery. Attentional load was manipulated by defining the target by its color (low load) or by both its color and orientation (high load). Consistent with prior work, younger adults inhibited visual cortex activation to the distracting checkerboards under high attentional load. However, this load-dependent suppression effect was not observed in older adults. This load-by-age interaction effect was significant, suggesting that unlike younger adults, older adults do not inhibit visual processing of irrelevant distractors as load increases. Surprisingly, the presence of peripheral checkerboard distractors under high attentional load improved, rather than impaired, older adults’ reaction times and increased their pupil dilation responses, suggesting that perceptual distractors may benefit late selective attention processes in aging. Additionally, we found greater prefrontal cortex engagement in older relative to younger adults under high attentional load. In summary, younger adults inhibit visual processing of distractors more effectively than older adults as central attentional load increases. However, under high task demands, an upregulation of arousal and prefrontal cortex processes may enable older adults to compensate for such inhibition deficits and improve task-focused attention.

A3 – Attentional modulation in early visual cortex: a combined re-analysis of steady-state visual evoked potential studies

Presenter

Nika Adamian

University of Aberdeen

Co-Author

SÃ¸ren Andersen

University of Aberdeen

Steady-state visual evoked potentials (SSVEPs) are a particularly powerful tool for investigating selective attention. The SSVEP is a continuous oscillatory response of the visual cortex that has the same fundamental frequency as the driving stimulus and whose amplitude is increased with attention to the driving stimulus. When multiple stimuli flickering at different frequencies are presented concurrently, each one of them will drive an SSVEP at its respective frequency, thereby allowing for the assessment of the allocation of attention to each element in a multi-stimulus display. Here we combined the data of eight published SSVEP studies in which participants (n=139 in total) attended to flickering random dot stimuli based on their defining features (e.g. location, color, luminance, or orientation) or feature-conjunctions. The reanalysis first established that in all the studies attention reliably enhanced amplitudes and shortened latencies of SSVEPs, with colour-based attention providing the strongest effect. Next we investigated the modulation of SSVEP amplitudes in a subset of studies where two different features were attended concurrently. While most models of feature-based attention assume that multiple features are combined additively, our results suggest that neuronal enhancement provided by concurrent attention is better described by multiplicative integration. Finally, we used the combined dataset to demonstrate that the increase in SSVEP amplitudes cannot be explained by the synchronization of single-trial phases. Contrary to the prediction of the phase locking account, the variance of complex Fourier coefficients increases with attention, which is more consistent with boosting of largely phase-locked signal with non-phase-locked noise.

A4 – Phenomenological and electrophysiological correlates of executive and affective mind wandering

Presenter

Paloma Manguele

University of Sussex, School of Psychology

Co-Author

Sophie Forster

University of Sussex, School of Psychology

Co-Author

Fiona Wiegert

University of Sussex, School of Psychology

Previous research has highlighted that mind-wandering can serve important functions such as planning for the future, decision making, and strategic problem solving relating to our current concerns. However, such ‘executive’ forms of mind wandering can also take negative forms in terms of worry. The goals of the present research were to characterize the phenomenology of executive forms of spontaneous mind wandering, in relation to both emotional valence and mental time travel, and to facilitate future research in this area by establishing objective electrophysiological markers for executive and affective dimensions of thought. To address our first goal, two large online studies (total N = 605) employed intermittent probes during an audio lecture at which participants rated and reported their thought contents. Thirty-eight percent of thoughts were rated as moderately or highly strategic. These ‘executive thoughts’ were more likely to be future-oriented than those rated as less strategic. Individual propensity to strategic thought predicted the prospective bias but was not consistently linked to thought valence or anxiety. We then asked 30 participants to perform a series of thought exercises designed to simulate mind wandering, varying in strategic content and emotional valence, while EEG and facial EMG data were recorded. More strategic thoughts and negative valence were reflected in increased frontal beta and activity of the corrugator supercilii muscle, respectively. Our findings hence provide the foundation for future research testing the ability of these objective electrophysiological markers to index executive and affective dimensions of spontaneous thought contents.

A5 – Measurement Properties of Pupillary Dynamics

Presenter

Alexis Torres

Arizona State University

Co-Author

Matthew Robison

The University of Texas at Arlington

Co-Author

Gene Brewer

Arizona State University

Pupillary dynamics partially index neuromodulatory signals from the noradrenergic and dopaminergic systems. These dynamics have been associated with a vast array of cognitively meaningful behaviors in the fields of perception, attention, and memory. In the current study, we sought to evaluate the psychometric measurement properties of pupillary dynamics across a set of attention tasks (Sustained Attention to Response Task, Psychomotor Vigilance Task, Color-Word Stroop Test, and Arrow Flanker Task) on two days of administration, separated by at least 6 days. Individual estimates of pupil size, pupil size variability, and pupil dilation in response to target stimuli were extracted for each task. We then measured within-task (split-half reliability) and between-task (convergent validity) correlations between these estimates. Overall, we found that individual differences in pupillary dynamics have strong psychometric properties that render them useful for evaluating individual differences. Moreover, pupillary dynamics were task general across 4 attention control tasks indicating that these dynamics likely reflect trait-like neuromodulation.

A6 – Single word and passage-level errors in patients with neglect dyslexia: A case series study

Presenter

Timothy Rich

Kessler Foundation

Co-Author

Olga Boukrina

Kessler Foundation

Co-Author

Peii Chen

Kessler Foundation

Individuals with spatial neglect (SN) following right brain damage distribute insufficient attention to the left side of space or objects. In the associated reading impairment, neglect dyslexia (ND), patients err on the left side of a word or omit words nearest the left margin of a passage of text. It remains unclear if the presence of one or both of these error types is related to lesion location or other SN characteristics. Here we compared lesion location and performance on a number of assessments for SN among three stroke survivors with SN – one ND+ patient with primarily passage-level errors, one ND+ patient with passage- and word-level errors, and one ND- patient with non-lateralized passage-level errors. Lesion analyses showed that the two ND+ patients had subcortical white matter (WM) lesions affecting superior and inferior longitudinal fasciculi while the ND- patient had a temporoparietal lesion sparing the longitudinal WM connections. The two ND+ patients also showed poorer performance on visual search (cancellation) tasks than the ND- patient. Thus, we observed neurologic and behavioral distinctions between ND+ and ND- patients, but no apparent difference between ND+ patients who have reading errors at different levels. The findings suggest that damage to association fibers that connect cortical areas within the same hemisphere results in a more severe spatial impairment and produces reading deficits. Further large-scale research is needed to study the neural basis of reading errors at single-word level versus passage level.

A7 – Multivariate approaches on electroencephalography highlight the breakdown of modularity in visuospatial attention

Presenter

Mathieu Landry

École Normale Supérieure

Co-Author

Jason Da Silva Castanheira

McGill University

Co-Author

Jerome Sackur

Ã‰cole Normale SupÃ©rieure

Co-Author

Amir Raz

McGill University

The modular view of visuospatial attention posits that stimulus- and goal-driven orienting represent functionally independent systems. This dichotomy largely follows from their respective mode of control, wherein stimulus-driven orienting corresponds to involuntary shifts of attention due to salient events and goal-driven attention reflects voluntary control of orienting responses. While a large body of findings support this general construal, research about how these orienting systems operate alongside each other remains scant. As a consequence, limited evidence validates the idea that they are completely separable. Capitalizing on single and double cueing approaches to contrast the effects of each form of orienting alone against that of both forms when they are concurrently engaged, our study (N=32) used electroencephalography (EEG) to assess the modular view and determine whether they operate independently at the neural level during the orienting response and ensuing target-related processing. Multivariate analyses of EEG signals where we decoded the effects of attention highlight the breakdown of modularity for both orienting and target processing. In particular, we observed that goal-driven attention interferes with stimulus-driven orienting, even when both systems are simultaneously engaged towards the same spatial location. Further analyses intimate that attention-related changes in posterior alpha waves underlie the permeability of modularity in visuospatial attention. Our findings shed light on the complex dynamics that support attention processing and demonstrate how competition characterizes the relationship between stimulus- and goal-driven orienting at the sensory level.

A8 – Inter-Network Neural Connectivity Mediates Intuitive Moral Decision-Making between Younger and Older Adults

Presenter

Shenyang Huang

Duke University

Co-Author

Leonard Faul

Duke University

Co-Author

Gunes Sevinc

Massachusetts General Hospital & Harvard Medical School

Co-Author

Laetitia Mwilambwe-Tshilo

McGill University

Co-Author

Roni Setton

McGill University

Co-Author

Amber W. Lockrow

McGill University

Co-Author

Natalie C. Ebner

University of Florida, Gainesville

Co-Author

Gary R. Turner

York University

Co-Author

R. Nathan Spreng

McGill University

Co-Author

Felipe De Brigard

Duke University

Older adults (OAs) occupy many positions of power and constitute an increasingly larger share of the population. These demographic shifts underscore the importance of studying age-related changes in decision-making, particularly when it comes to difficult, morally-laden scenarios. However, little is known about age-related differences in moral decision-making and their relationship to the intrinsic network architecture of the brain. In the present study, younger adults (YAs; n = 117, Mage = 22.11) and OAs (n = 82, Mage = 67.54) made decisions on multiple hypothetical moral dilemmas and completed resting-state multi-echo fMRI scans. Relative to YAs, OAs were more likely to endorse deontological decisions and favor an action consistent with a moral principle, but only when the deontological moral choice was intuitive. By contrast, OAs’ decision-making did not differ from that of YAs when the utilitarian moral choice was intuitive. Enhanced connections between the posterior medial core of the default network (pmDN) and dorsal attention network , as well as overall reduced segregation of the pmDN from the rest of the brain, partially mediated this increased deontological-intuitive moral decision-making style in OAs. The present study provides novel insight into the differential network connectivity associated with moral reasoning in YAs and OAs, expanding our understanding of the diversity of neurocognitive changes that accompany aging.

A9 – Neural basis for the processing of pain psychomimes: A functional magnetic resonance imaging study

Presenter

Qiong Ma

National Rehabilitation Center for Persons with Disabilities

Co-Author

Sachiko Kiyama

Tohoku University

Co-Author

Michiru Makuuchi

National Rehabilitation Center for Persons with Disabilities

Pain psychomimes, a kind of Japanese onomatopoeias, help patients to effectively complain their pain. Psychomimes are supposed to yield emotional empathy in the other, since they vividly depict the speaker’s inner life. We performed fMRI to reveal the neural basis for the empathy processing via pain psychomimes (34 participants). Three types of sentences were examined. The first was sentences with a psychomime, like ‘I had a toothache zukizuki.’. The second was the same as the first, but with an adverb of degree instead of a psychomime, e.g., ‘I had a toothache strongly.’. The last described a painful event such as ‘I twisted my ankle on the playground’. The fMRI data were collected while participants read those sentences and rated the intensity of pain in four levels. We found that the activities in the empathy-related brain regions including the anterior cingulate cortex and anterior insula were correlated with the pain intensity ratings, especially for the psychomimes than for the adverbs. This suggests the superiority of psychomimes for arousing emotional empathy. A direct comparison revealed higher activation in the anterior and middle portion of middle temporal gyrus, pars opercularis bilaterally and in left anterior superior temporal gyrus in the adverb condition than in the psychomimes condition. This result suggests that adverbs require extra computational cost than psychomimes. Taken together, these findings fit well with the native Japanese speakers’ preferential use of psychomimes for depicting their pain because of the efficacy of invoking empathy and the lower neural computational cost.

A10 – Emotion Regulation Training Induces Wide-Spread Changes in Functional Activation and Connectivity

Presenter

Olivia Cook

University of Louisville

Co-Author

Jessi Kane

University of Louisville

Co-Author

Karisa Hunt

University of Louisville

Co-Author

Brendan Depue

University of Louisville

‘Brain Training’ programs are becoming more ubiquitous in mainstream society. However, there are relatively few studies exploring whether specific task related training leads to functional plasticity in the brain. Furthermore, no studies exist, to our knowledge, that explore training an individual’s ability to down-regulate emotion reactivity. Importantly, understanding which neural regions show changes across training highlights important brain mechanisms involved in emotion regulation processes; processes which are critical to efficient daily functioning. We explored this question using fMRI before and after emotion regulation training. Eighteen undergraduate students were recruited in a 5-day training study. Participants were scanned on day 1 and day 5. The emotion regulation task and training consisted of a standard emotion regulation paradigm, in which participants were asked to down-regulate their physiological response to negatively valanced IAPS pictures. A subjective emotion ratings task was performed before (baseline) and approximately 30 minutes later (ER-rating) required participants to interrogate their subjective emotional feeling toward IAPS pictures. Behaviorally, a significant decrease in subjective negative emotion ratings occurred on day 5 compared to day 1 (p<.03; M=2.1/2.6). Functional analyses revealed decreased activation in the dorsal medial prefrontal cortex (dmPFC), right inferior and middle frontal gyri (rIFG/rMFG), and both ventral and dorsal amygdalae on day 5 compared to day 1. Conversely, increased activation was seen in the orbitofrontal cortex (OFC) on day 5 compared to day 1. Using the above regions in functional connectivity analyses, revealed that while functional activation decreased, increased functional connectivity was observed in the rMFG-OFC and OFC-amygdalae.

A11 – Representations of concepts diverge according to the emotional value.

Presenter

martina riberto

Co-Author

Rony Paz

Weizmann Institute of science

Co-Author

Gorana Pobric

University of Manchester

Co-Author

Deborah Talmi

University of Cambridge

Background. Emotional and neutral concepts are represented in different brain regions. However, it is still unknown whether the emotional value of each stimulus is encoded separately or integrated in semantic and high-level visual regions. This is of paramount importance for the debate in semantic cognition on organisation of semantic memory, and for possible treatments of anxiety disorders. Methods. 29 participants took part in a functional Magnetic Resonance Imaging (fMRI) experiment where they performed a visual complexity rating of 72 complex pictures, which depicted 4 categories of realistic events (2 neutrals and 2 negative emotional). After, participants arranged these pictures in a bidimensional space, according to the similarity among them. In two separate searchlight Representation Similarity Analyses (RSA), we correlated participants’ neural pattern activations and their perceived similarity within emotional (EE) and neutral (NN) categories (pFDR <0.05). Results. NN was correlated with clusters in the bilateral occipital place area (OPA) and parahippocampal place area (PPA). In addition to OPA and PPA, EE correlated with clusters in the bilateral precuneus, dorsal anterior cingulate cortex (dACC) and left anterior insula. EE and NN correlations significantly differed, with EE showing higher correlations between neural pattern activations and participants’ similarity space (pFWE <0.05).
Conclusions. Representations of concepts inherent to realistic events are grounded in high-level visual regions, including the OPA and PPA. The emotional value is separately encoded in areas involved in emotional processing and regulation. This suggests that concepts formation relies on the interaction between regions that code relevant stimulus properties.

A12 – Arousal enhances memory selectivity in young but not older adults: fMRI and behavioral evidence

Presenter

Sara Gallant

University of Southern California

Co-Author

Sara Gallant

University of Southern California

Co-Author

Briana Kennedy

University of Western Australia

Co-Author

Ringo Huang

University of California, Los Angeles

Co-Author

Mara Mather

University of Southern California

In young adults, increases in arousal selectively enhances memory for salient information while suppressing memory for non-salient details. This adaptive response helps us to perform during high-stake moments by focusing attention on important information amid distraction. However, these processes are thought to change with age. Older adults show a decline in the ability to ignore distraction as well as changes in the arousal system, which threaten to disrupt arousal’s ability to coordinate selective processing. Here, we used fMRI to test the hypothesis that increases in arousal amplify memory and neural selectivity for young adults but not for older adults. While in an MRI scanner, participants completed an attention selectivity task where they heard an arousing or neutral sound followed by two category-specific stimuli that were competing in perceptual salience. On an incidental memory task, young adults remembered more of the salient than non-salient stimuli on arousing relative to neutral trials whereas older adults did not show an increase in memory selectivity under arousal. Hearing an arousing sound also increased young adults’ brain activity in category-selective ventral occipitotemporal cortex (extrastriate body area) when viewing salient vs. non-salient stimuli. By contrast, arousal did not modulate older adults’ brain activity in response to stimuli. These behavioral and fMRI findings suggest that arousal becomes less effective at enhancing selective processing in the aging brain.

A13 – The role of autobiographical memories in empathy

Presenter

Federica Meconi

University of Birmingham

Co-Author

NicolÃ² Di Lello

University of Padova

Co-Author

Alessio Avenanti

University of Bologna

Co-Author

Carlo Miniussi

Center for Mind/Brain Sciences

Co-Author

Carmel Mevorach

University of Birmingham

Empathy is the ability to understand and share others’ inner states and therefore is critical in interacting behaviour. A significant body of research has shown that autobiographical memory (AM) plays an important role in empathic processes. In two recent studies (N = 28 each) we provided behavioural, EEG and fMRI evidence for online reactivation of the AM during the preparation of empathic judgments. However, a causal relation between AM and empathy (i.e., whether AM directly drives empathy judgements) has not been proven. Using similar paradigm, we conducted a study (N = 5, interrupted by coronavirus-related lockdown) in which we used transcranial magnetic stimulation (TMS) with the aim to interfere with the AM retrieval during an empathy task. Healthy students had to judge their empathy awareness for individuals as depicted in contexts described by a sentence. The contexts described episodes of intense physical pain or neutral events for which participants did or did not have an AM. For each trial, a burst of three TMS pulses was delivered in a specific time-window to the left superior parietal lobule (SPL), a brain region involved in the AM retrieval. We sought to testing whether interfering with AM retrieval, due to the stimulation of the SPL, would cause reduced empathic reactions as expressed on a behavioural level by the empathy judgements. Although preliminary, this set of results shows promising suggestion that AM drives explicit judgments of empathy.

A14 – Understanding Others Requires Right Temporoparietal Junction

Presenter

Tatiana Schnur

Baylor College of Medicine

Co-Author

Junhua Ding

Baylor College of Medicine

Co-Author

Margaret Blake

University of Houston

The human ability to infer other people’s knowledge and beliefs, known as ‘theory of mind’, is an essential component of social interactions. Theory of mind tasks activate frontal and temporoparietal regions of cortex in fMRI studies. However, it is unknown which of these regions are critical. We examined this question using voxel-based lesion symptom mapping in 20 patients with acute right hemisphere brain damage. Studies of acute patients sidestep questions of recovery and reorganization that plague long-term studies of lesioned patients. Damage to the temporoparietal junction but not frontal cortex impaired thinking about others’ perspectives. This impairment held even after adjustment for overall extent of brain damage and memory, comprehension, and attention abilities. These results provide evidence that right temporoparietal junction is necessary for the human ability to reason about the knowledge and beliefs of others.

A15 – Reward prediction error signals in the amygdala selectively guide social learning under uncertainty

Presenter

Amrita Lamba

Brown University

Co-Author

Matt Nassar

Brown University

Co-Author

Oriel FeldmanHall

Brown University

Learning about others’ trustworthiness often serves as an informative cue of social rewards, particularly in highly uncertain situations. While considerable research efforts have focused on nonsocial reward learning, much less is known about the neural computations supporting social reward learning. More specifically, how do humans learn to trust? Here we leverage computational neuroimaging approaches to investigate how individuals learn about information along value and uncertainty dimensions. We then examine how this knowledge is exploited to build a representation of trustworthiness that can adaptively guide social choice. Using the Trust Game (TG) and a matched nonsocial slot machine (SM) task, we examined how swiftly participants (N = 28) learned to make reward-maximizing choices across these contexts. Social partners and slot machines were preprogrammed to drift in their trustworthiness/monetary reward across the task. Compared to nonsocial SMs with matched reward distributions, results reveal that participants were faster to learn and experienced fewer reward prediction errors (RPEs) when interacting with consistently trustworthy or selfish partners, which correlated with activation of the striatum. In contrast, when interacting with social partners who indiscriminately showed trustworthy and untrustworthy behavior (i.e., highly uncertain behavioral profiles), participants were slower to learn and experienced greater RPEs during the TG compared to the SM. RPEs associated with learning about uncertain social partners uniquely scaled with activity in the amygdala, whereas the striatum indexed learning about uncertain SMs. These results suggest that context-selective representation of RPEs in the amygdala and striatum may drive asymmetrical learning profiles across social and nonsocial environments.

A16 – Why do children have lower working memory precision than adults? Examining the role of attentional allocation with pupil

Presenter

Elena Galeano Weber

DIPF Leibniz Institute, Frankfurt am Main

Co-Author

Sarvenaz Pakzad

University of California, Berkeley

Co-Author

Garvin Brod

DIPF Leibniz Institute, Frankfurt am Main

Co-Author

Silvia Bunge

University of California, Berkeley

Developmental studies of working memory (WM) have largely focused on increased capacity – that is, the number of items that can be remembered – and not the fidelity of these representations. Here, we examined visual WM fidelity in terms of recall precision and recall variability in middle childhood and young adulthood. We tested whether differences in WM fidelity could reflect differences in sustained attention at encoding and/or across a delay period. To this end, we probed color precision of each of three sequentially encoded objects. Using pupil dilation as a moment-to-moment measure of attentional allocation, we measured attentional allocation at encoding and throughout a long delay period. Consistent with recent behavioral research, adults showed higher recall precision and exhibited lower recall variability than children. Adults had larger pupillary responses than children during encoding, but smaller responses during the delay period, suggesting differential allocation of attention across the trial. Among children, higher WM fidelity was linked to smaller pupillary responses during encoding and maintenance, suggesting that WM processing may rely on more efficient attentional allocation with increasing expertise. Finally, we provide tentative evidence that more sustained attention as indicated by lower fluctuations in pupil dilation towards the end of a long delay period might help children exhibit more stable WM performance.

A17 – Age is Associated with Whole-Brain Structural Topology but not Resting State Functional Topology in Older Adults

Presenter

DANIEL ELBICH

Hershey Medical Center

Co-Author

Suzanne Segerstrom

University of Kentucky

Co-Author

Jonathan Hakun

Hershey Medical Center

Human aging is associated with alterations to brain structure and function. While the effects of aging on indicators of resting state functional connectivity (e.g., default-mode network timeseries correlations) and white matter microstructure (e.g., fractional anisotropy) have been well studied, how aging alters whole-brain cortical structural and functional network topology remains poorly understood. Whole-brain connectomic analysis represents an approach to examining network topology that can be applied to both functional and structural data. A sample of 76 older adults (range: 60-95) underwent resting state fMRI and diffusion-weighted MRI scanning. Parcellation was conducted using the Schaefer 17 Network, 400 parcel atlas. Following preprocessing, BOLD timeseries correlations were carried out on the resting state fMRI data between the 400 parcels to construct the resting state functional network. Whole-brain probabilistic, surface-based tractography analysis, informed by the Human Connectome Project pipeline, was conducted on the diffusion-weighted data to construct the structural network. The resulting functional and structural connectomes were then quantified using graph theoretical metrics. Our results indicated that age was significantly associated with multiple measures of structural network topology: density (p < 0.01), global efficiency (p < 0.05), and modularity (p < 0.001). However, no significant associations between age and any measure of functional network topology was observed. Further, structural and functional network topology measures were not inter-related before or after controlling for age. Overall, our results suggest that summary measures of whole-brain white matter structural topology, but not functional network topology, are consistent with previously observed age-associated differences in network- and modality-specific indicators.

A18 – Transient control and global-sustained control mechanisms in bilingual aphasia

Presenter

Lesley Peng

San Francisco State University

Co-Author

Teresa Gray

San Francisco State University

Bilinguals control two languages. This skill may transfer to a nonverbal cognitive benefit, yet the relationship between verbal control and nonverbal control is unclear. Because bilingual people with aphasia (BPWA) may present with language control and cognitive control deficits, they are a unique population to study control mechanisms. Data were collected from 8 Spanish-English BPWA and 11 Spanish-English age-matched bilingual adults (AMBA). Participants completed a nonverbal color/shape switching task including bivalent conditions (to elicit inhibition of non-target domain) and a verbal Spanish-English switching task. The experimental structure was a sandwich design: two single blocks, three mixed blocks, two single blocks. Single blocks include single trials. Mixed blocks include nonswitch and switch trials. Switch-costs (higher accuracy/faster response time [RT] on non-switch vs switch trials in the mixed block) that tap transient control mechanisms and mixing-costs (higher accuracy/faster RTs on single trials in single block vs non-switch trials in the mixed block) that tap global-sustained control mechanisms were examined. All reported results are significant at p < .05. Separate paired- samples t-tests were performed for each group to evaluate the switch-cost and mixing-cost on both tasks. Verbal results: AMBA exhibited switch-cost for accuracy and RT in English, and both AMBA and BPWA exhibited switch-cost for RT in Spanish. Nonverbal results: BHA and BPWA exhibited mixing-cost for accuracy in color condition, and RT for color and shape condition. Results suggest a dissociation between costs across domains for both groups, indicating that BPWA management of transient and global control mechanisms is similar to AMBA.

A19 – Theta oscillations shift towards optimal frequency for cognitive control

Presenter

Mehdi Senoussi

Ghent University

Co-Author

Pieter Verbeke

Ghent University

Co-Author

Kobe Desender

Ghent University, KU Leuven

Co-Author

Esther De Loof

Ghent University

Co-Author

Durk Talsma

Ghent University

Co-Author

Tom Verguts

Ghent University

Humans’ capacity to pursue goal-oriented behavior despite changes in the environment is uniquely flexible. Cognitive control refers to processes allowing such behavioral adjustments and critically relies on neural oscillations in the theta band (4-7Hz). Theta amplitude has been shown to increase when control is needed, however, it remains largely unknown how theta oscillations support flexible adaptation to task demands. In this study we show that an essential aspect of theta oscillations has been completely overlooked so far: its specific frequency in the 4-7Hz range. We built a novel computational model in which theta oscillations orchestrate control over sensory and action representations, by establishing task-relevant functional networks through synchronization. Critically, we show that the frequency of theta oscillations balances reliable set up of task rules and gating of task-relevant information. Our model additionally predicts that this theta-rhythmic process is observable in behavioral performance, which constitutes, to our knowledge, the first time this phenomenon is predicted from computational simulations. We tested these predictions using a stimulus-response mapping task, and recorded EEG, in 33 participants. We showed that both behavioral performance and mid-frontal theta activity oscillated at slower frequency with increasing task difficulty. Furthermore, we showed that this shift in neural theta predicted trial-by-trial behavioral performance and that the sensitivity of theta frequency to task demands predicted overall task performance across participants. Our study provides a novel computational framework proposing how theta oscillations mechanistically implement cognitive control and adapt to external demands, opening new avenues for research on the regulation of cognitive control.

A20 – Psychosocial Stress Modulates Performance and Neural Information Processing during a Go/NoGo Task

Presenter

Chrystal Spencer

Rutgers University, Newark, NJ, USA

Co-Author

Ravi D. Mill

Rutgers University, Newark, NJ, USA

Co-Author

Jamil Bhanji

Rutgers University, Newark, NJ, USA

Co-Author

Mauricio Delgado

Rutgers University, Newark, NJ, USA

Co-Author

Michael W. Cole

Rutgers University, Newark, NJ, USA

Co-Author

Elizabeth Tricomi

Rutgers University, Newark, NJ, USA

Psychosocial stress affects learning, memory, and attention, but the influence of stress on the neural processes supporting cognitive performance remains unclear. We investigated how psychosocial stress influences performance and neural processing during a Go/NoGo task. Eighty participants either underwent the Trier Social Stress Test (TSST) stress induction, or completed personality questionnaires as a control condition. Then, participants completed an fMRI Go/NoGo task, with blood pressure and salivary cortisol measurements taken intermittently. The TSST was successful in eliciting a stress response, as indicated by subjective stress ratings (t = -9.57, p < 0.001) and change in systolic blood pressure (t = -2.47, p = 0.018). Participants who underwent the TSST made fewer commission errors on trials requiring the most inhibitory control relative to the control group (t = -2.86, p = 0.026), suggesting increased vigilance. Univariate GLM analysis of task brain activity revealed no between-group differences for any region. However, using multivariate pattern analysis, stress and control groups were differentiated in the medial intraparietal area (mIPA, affiliated to the dorsal attention network; classification accuracy (CA) = 69.4%; FDR-corrected p = 0.045); the cerebellum (default mode network; CA = 72.2%; p = 0.019); and the brainstem (visual network; CA = 70.8%, p = 0.025). The mIPA and the cerebellum have been implicated in visuomotor coordination, a function central to goal-directed behavior. These results suggest that stressor-induced hypervigilance can have a facilitative effect on cognitive performance which is represented neurally by the activation patterns of cognitive control regions.

A21 – Response inhibition in schizophrenia: neural mechanisms revealed by the P3 and lateralized readiness potential

Presenter

Xiangfei Hong

Shanghai Mental Health Center

Co-Author

Fuzhong Yang

Shanghai Mental Health Center

Co-Author

Yegang Hu

Shanghai Mental Health Center

Co-Author

Zhenying Qian

Shanghai Mental Health Center

Co-Author

Jijun Wang

Shanghai Mental Health Center

Co-Author

Chunbo Li

Shanghai Mental Health Center

Co-Author

Jianhua Sheng

Shanghai Mental Health Center

Schizophrenia is characterized by increased impulsivity and poorly planned behavior, which may originate from a deficit in the response inhibition system. We hypothesized that inhibition deficits in schizophrenia might depend on the specific levels of response tendencies that need to be inhibited. To test this hypothesis, we analyzed the event-related potential marker of response inhibition, i.e., P3, recorded from 29 schizophrenia patients (SZs; 17 women; mean age: 30.4 years) and 31 healthy control subjects (HCs; 17 women; mean age: 29.1 years) in a combined flanker-Go/NoGo task. The response tendency level in each NoGo trial was quantified by its lateralized readiness potential (LRP). For each subject, the NoGo trials were sorted into 3 groups according to their response tendency levels, i.e., single-trial LRPs. Behaviorally, we found that although SZs showed lower NoGo accuracy than HCs (p = 0.016), the NoGo accuracy decreased as the response tendency level increased in both groups (p = 0.003). For P3, the two-way ANOVA did not reveal significant main effect of group (p = 0.481), but reveal a significant interaction between response tendency and group (p = 0.003). Further tests suggested that only HCs showed significantly increased P3 amplitudes as the response tendency level increased (p = 0.019). In contrast, SZs showed a trend of decreased P3 amplitudes as the response tendency level increased (p = 0.125). Together, these results support our hypothesis by suggesting that the failure to increase P3 amplitudes in response to increased response tendency levels might underlie the inhibition deficits in SZs.

A22 – Investigating the Relationship Between Aerobic Fitness and Performance Across Cognitive Domains in Healthy Young Adults

Presenter

Alexander Stuber