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Behavioural and electrophysiological measurements of lapses in sustained auditory attention Poster A1, Saturday, March 24, 1:30–3:30 pm, Exhibit Hall C Alice E Milne1, Daniel I R Bates1, Maria Chait1; 1UCL, London Top-down attention during noisy auditory scenes boosts perception of task-relevant stimuli, while inhibiting irrelevant signals. However, sustaining attention over extended periods of time is challenging and leads to lapses in attention. Recordings from macaque auditory cortex show that neural alpha-oscillations and entrainment reflect transient changes in attentional state. However, it is unknown how the human neural response to auditory stimuli is affected by attentional lapses. We designed a novel paradigm to study unintentional breaks in sustained attention. Participants were required to track pitch changes in a pure-tone pulse stream. To increase perceptual load, the target stream was flanked by two additional pulse-streams of different pitch and pulse rates, along with attention-capturing high-pitch tone pips and a flickering visual Gabor-patch. Trials were 5-mins long with behavioural responses captured semi-continuously (2-7 seconds). Critically, control trials presented the same auditory and visual stimuli but participants performed a low-attention task, responding to the salient tone pips or Gabor orientation changes. Variations in false alarms, misses and reaction times were used to identify periods when attention to the target stream lapsed. EEG data was acquired using the same paradigm and the behavioural data used to determine the occurrence of attentional lapses. These time periods were then used to characterise the dynamic neural changes that result from variations in attentional states, specifically for alpha-band activity and neural entrainment. We report a novel paradigm that behaviourally captures transient changes in top-down attention, and which can be used to effectively study the neural features of an attentional lapse. Topic Area: ATTENTION: Auditory Anticipatory EEG Activity during Somatosensory Selective Attention relates with Executive Function Poster A2, Saturday, March 24, 1:30–3:30 pm, Exhibit Hall C Staci Meredith Weiss1, Rebecca Laconi1, Peter Marshall1; 1Temple University There is growing evidence that the ability to selectively attend to target stimuli is related to higher-order cognitive skills. We examine whether sensorimotor oscillatory EEG activity during anticipation of tactile stimulation is related to executive function (EF) in adults. During EEG collection, a visual cue directed participants’ attention to their right or left hand in preparation for tactile stimulation. Tactile stimulation was delivered via inflatable membranes attached to the index finger of the participant’s hands. Participants (N=20) also completed 3 EF tasks on the NIH Cognitive Toolbox, which included measures of behavioral inhibition (flanker), working memory and task-switching (card sort). Analyses focused on the amplitude and lateralization of the sensorimotor mu rhythm (8 – 13 Hz) during anticipation of tactile stimulation. Mu rhythm amplitude was related to the interaction between hemisphere and target hand, F = 5.57, p = .02. We observed a significant reduction in amplitude over the somatosensory cortex contralateral to the target hand, and no significant change over the ipsilateral somatosensory cortex. Further analyses related scores on EF tasks with contralateral mu rhythm activity. Results indicate that contralateral EEG activity was related to the working memory task, F= -5.30, p < .01 and marginally related to the behavioral inhibition task, F = -1.93, p = 0.06. These findings extend the literature on selective attention and EF by indexing attention to a modality (somatosensory) which is not involved in EF tasks. We discuss implications for the malleability of selective attention and development of EF. Topic Area: ATTENTION: Multisensory Default-Executive coupling in attention control after traumatic brain injury with task functional magnetic resonance imaging in longitudinal study. Poster A3, Saturday, March 24, 1:30–3:30 pm, Exhibit Hall C Shun-Chin Wu1,2, Lei Wang1, Fan-pei Gloria Yang3, Furen Xiao4; 1Northwestern University, Chicago, IL 60611, USA, 2National Defense Medical Center, School of Medicine, Taipei, Taiwan, 3National Tsing Hua University, Hsinchu, Taiwan, 4National Taiwan University Hospital, Taipei, Taiwan Deficits in goal-oriented executive function such as working memory are common in individuals with Traumatic Brain Injury (TBI). Recent longitudinal neuroimaging studies showed increased activation and connectivity in TBI patients. During a 5-week observation period, we examined changes in goal-oriented executive function in 21 patients with brain injury in post-acute phase, using a face/scene matching 1-back functional magnetic resonance imaging (fMRI) task (Chen, 2012). The block-design fMRI task involved two types of interleaving stimuli: relevant and irrelevant, depending on whether the current stimulus matched the goal category (face or scene). We used multivariate pattern analysis (MVPA) to assess the relevant vs. irrelevant stimuli contrast as indication of clarity for different types of information. All data were preprocessed in SPM 12 with The Decoding Toolbox for MVPA, followed by repeat-measures ANOVA to examine longitudinal change, with a cluster FWER p=.001. Results showed that task accuracy did not change significantly. Significant increases were found in the right dorsolateral prefrontal cortex (DLPFC), right putamen and bilateral premotor cortex, and decreases in the posterior cingulate cortex (PCC), precuneus and right middle temporal gyrus in averaged information map. The combined decreases in PCC and precuneus were correlated with the increases in right DLPFC (r=-0.441, p=0.043), as with right DLPFC and putamen (r=-0.526, p=0.015). These anticorrelated changes in the executive, salience and default model networks in post-acute phase TBI patients suggest neural functional recovery at five-week follow-up that may precede any performance change. Our study can provide useful information regarding appropriate timing for future neurorehabilitation management. Topic Area: ATTENTION: Nonspatial Estimation of Mind-Wandering - For the Respondent Conditioning Enhancing the Meta- Awareness Ability to Mind-Wandering Poster A4, Saturday, March 24, 1:30–3:30 pm, Exhibit Hall C Issaku Kawashima1,2, Hiroaki Kumano1, Keiko Momose1; 1Faculty of Human Sciences, Waseda University, 2Graduate School of Human Sciences, Waseda University Mind-wandering (MW) is a thought unrelated to the current tasks. Though the trait to be meta-aware of MW might ameliorate depression and increase creativity, the means to enhance the ability of meta-awareness in an individual is not known. Meta- awareness cannot be attended when one is absorbed in MW. But if one’s attention is directed to external stimulus so that MW is interrupted, the person can be made meta-aware of incidences of mind-wandering. Conducting respondent conditioning between an occurrence of MW and an arousal of external attention (i.e., whenever someone slips into the state of MW, the person’s attention is directed to the outside) possibly helps enhance meta-awareness ability. The method of detecting MW is crucial for such conditioning protocols that need the detection of MW and the immediate presentation of the stimulus. This study aims to indicate that electroencephalogram (EEG) can estimate the intensity of MW. Fifty people participated in the experiment. We measured their EEG during the performance of sustained attention to response task (SART) with experience sampling questions on how strongly they executed MW. We applied support vector machine regression on the EEG features, including eight frequency band power and coherence of 17 channels, and created a model estimating MW intensity. The verification with hold-out data indicated the robustness of this model (r = .49). The result suggests that MW intensity can be estimated by EEG and the feasibility of respondent conditioning with MW estimation by EEG measuring. This presentation was supported by Tateisi Science and Technology Foundation. Topic Area: ATTENTION: Other Characterizing the influence of attentional state on the fidelity and connectivity of stimulus representations across large-scale brain networks Poster A5, Saturday, March 24, 1:30–3:30 pm, Exhibit Hall C David Rothlein1, Joseph DeGutis1,2, Michael Esterman1,3; 1VA Boston Healthcare System, 2Harvard Medical School, 3Boston University School of Medicine Attention is thought to modulate performance by facilitating the representation of task-relevant features (representational fidelity) and integrating this information with task-rule representations (representational connectivity). However, attention is not a constant but fluctuates between stable/accurate (in-the-zone) and variable/error-prone (out-of-the-zone) states. Here we ask how different attentional states affect the neural processing and transmission of task-relevant information. Specifically, during in-the-zone vs. out-of-the-zone periods: (1) Do neural representations of task stimuli have greater fidelity? (2) Is there increased communication of this stimulus information across large-scale brain networks? We used fMRI and representational similarity analysis during a visual sustained attention task (the gradCPT) to address these questions. Participants (N=146) viewed a series of city or mountain scenes, responding to cities (90% of trials) and withholding
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