Association of deficits in short-term learning and Aβ and hippocampal volume in cognitively normal adults

ObjectiveTo determine the extent to which deficits in learning over 6 days are associated with β-amyloid–positive (Aβ+) and hippocampal volume in cognitively normal (CN) adults.MethodsEighty CN older adults who had undergone PET neuroimaging to determine Aβ status (n = 42 Aβ− and 38 Aβ+), MRI to determine hippocampal and ventricular volume, and repeated assessment of memory were recruited from the Australian Imaging, Biomarkers and Lifestyle (AIBL) study. Participants completed the Online Repeatable Cognitive Assessment–Language Learning Test (ORCA-LLT), which required they learn associations between 50 Chinese characters and their English language equivalents over 6 days. ORCA-LLT assessments were supervised on the first day and were completed remotely online for all remaining days.ResultsLearning curves in the Aβ+ CN participants were significantly worse than those in matched Aβ− CN participants, with the magnitude of this difference very large (d [95% confidence interval (CI)] 2.22 [1.64–2.75], p < 0.001), and greater than differences between these groups for memory decline since their enrollment in AIBL (d [95% CI] 0.52 [0.07–0.96], p = 0.021), or memory impairment at their most recent visit. In Aβ+ CN adults, slower rates of learning were associated with smaller hippocampal and larger ventricular volumes.ConclusionsThese results suggest that in CN participants, Aβ+ is associated more strongly with a deficit in learning than any aspect of memory dysfunction. Slower rates of learning in Aβ+ CN participants were associated with hippocampal volume loss. Considered together, these data suggest that the primary cognitive consequence of Aβ+ is a failure to benefit from experience when exposed to novel stimuli, even over very short periods.

Virtual reality telerehabilitation for spatial neglect post-stroke: perspectives from stroke survivors, carers and clinicians

Spatial neglect is a common and severe cognitive consequence of stroke, yet there is currently no effective rehabilitation tool. Virtual Reality (VR) telerehabilitation tools have the potential to provide multisensory and enjoyable neuropsychological therapies and remotely monitor adherence without the presence of a therapist at all times. Researchers and industry need to better understand end-user perspectives about these technologies to ensure these are acceptable and user-friendly and, ultimately, optimize adherence and efficacy. Therefore, this study aims to explore end-user perspectives on the use of self-administered VR telerehabilitation for spatial neglect to identify barriers and facilitators of use. We used a mixed-method design including focus groups, self-administered questionnaires and individual interviews with stroke survivors (N = 7), their carers (N = 3) and stroke clinicians (N = 6). End-user perspectives identified clarity of instructions, equipment (cost, available resources) and for some, level of experience with technology as barriers of use. Perceived facilitators of use were performance feedback, engagement and enjoyment, and psychological benefits associated by self-administered VR telerehabilitation. Overall, end-users were positive and interested in using VR telerehabilitation for spatial neglect. These perspectives enabled us to produce practical recommendations to inform development, enhance engagement and uptake of self-administered VR telerehabilitation and inform feasibility and usability studies.

Time, tense and viewpoint shift across languages: A Multiple-Parallel-Text approach to “tense shifting” in a tenseless language

The paper discusses the role of tense and time from a cross-linguistic perspective by comparing English (a tensed language) and Mandarin (a language without formal tense marking). Multiple translations of the same literary piece are used to test the correspondence between the tense, the perfective aspect and temporal adverbials. In English, tense marking is found to work with at least two language-specific stylistic means, clause interpolation and inversion, to create a mixed narrative viewpoint. In Mandarin, neither the perfective aspect nor temporal adverbials, i.e., constructions that invoketime, are systematically used across the renditions, which shows the Mandarin system’s overall indifference totimein managing viewpoint in discourse. The Mandarin renditions, in addition to an overall indifference totime, feature consistent and frequent use of reduplication as the system’s distinctive viewpoint strategy. The paper concludes with a discussion of the cognitive consequence of a language using an obligatory marking system to piggyback the function of viewpointing narratives.

The Enhanced Working Memory Model

This chapter traces the origins and currents of Frederick Coolidge’s collaborations with archaeologist Thomas Wynn. It begins with their first article, in 2001, in which they traced a cultural explosion some 50,000 years ago in the archaeological record (as attested by the appearance of things like cave paintings, highly ritualized burials, depictive figurines) to enhanced executive functions (i.e., temporal sequencing, inhibition, planning, and organization) that perhaps resulted from an earlier genetic or epigenetic event not shared by Neandertals. As evidence of enhanced executive functioning in Homo sapiens, Wynn and Coolidge offered barbed points from Katanda, bow-and-arrow technology, agriculture, and the colonization of the Sahul. In their more recent papers, they labeled the cognitive consequence of this genetic event enhanced working memory, thus incorporating their ideas into Baddeley’s multicomponent model of working memory. The chapter ends with speculations on the evolutionary origins of learning and memory systems, looking back to the very beginnings of life on earth.