The “Narratives” fMRI dataset for evaluating models of naturalistic language comprehension

The “Narratives” collection aggregates a variety of functional MRI datasets collected while human subjects listened to naturalistic spoken stories. The current release includes 345 subjects, 891 functional scans, and 27 diverse stories of varying duration totaling ~4.6 hours of unique stimuli (~43,000 words). This data collection is well-suited for naturalistic neuroimaging analysis, and is intended to serve as a benchmark for models of language and narrative comprehension. We provide standardized MRI data accompanied by rich metadata, preprocessed versions of the data ready for immediate use, and the spoken story stimuli with time-stamped phoneme- and word-level transcripts. All code and data are publicly available with full provenance in keeping with current best practices in transparent and reproducible neuroimaging

Semantics of Auditory Neglect

Auditory neglect exists when a person who has a brain lesion does not perceive an auditory stimulus in one ear when stimuli are presented binaurally or dichotically. The first aim of the current study was to simulate auditory neglect in participants with normal auditory perception using an experimental model of auditory neglect. This study hypothesized that when semantically related words were presented dichotically the simulated auditory neglect would be attenuated but not with unrelated words. Forty-five participants with normal auditory perception listened to the words pairs in a dichotic listening task in which the left ear was masked with noise. The experimental task was able to simulate auditory neglect and semantically related words were reported more than unrelated words. A second experiment was conducted to determine brain areas mediating the semantic system using functional Magnetic Resonance Imaging (fMRI). It was hypothesized that brain activation would be lateralized to the left hemisphere during auditory processing of semantic stimuli and there would be a difference in activation for semantically related words compared to non-semantically related words. Seventeen healthy, neurologically normal participants underwent fMRI scanning during which they listened semantic and non-semantic word pairs presented dichotically and judged if the words were related in meaning. Activation was lateralized to the left for the task. Both semantic and non-semantic conditions showed activation throughout the left frontal and temporal lobes. Direct comparison of the semantic and the non-semantic conditions did not yield different localization patterns.M.S., Psychology -- Drexel University, 201

Context-dependent memory effects in VR

The context-dependent memory effect, in which memory for an item is better when the retrieval context matches the original learning context, has proved to be difficult to reproduce in a laboratory setting. In an effort to identify a set of features that generate a robust context-dependent memory effect, we developed a paradigm in virtual reality using two semantically distinct virtual contexts: underwater and Mars environments, each with a separate body of knowledge (schema) associated with it. We show that items are better recalled when retrieved in the same context as the study context; we also show that the size of the effect is larger for items deemed context-relevant at encoding, highlighting the importance of integrating items into an active schema in generating this effect