Prospective memory,working memory,planning, and attention in schizophrenia and bipolar disorder: A comparative study

There is a need to study prospective memory (PM) and its relationship with aspects of frontal lobe functioning in schizophrenia and bipolar disorder. The study aims to investigate event‐based (EB) and time‐based (TB) PM functioning in the two groups, and its association with working memory, planning, and attention. A word categorisation task was developed to assess PM functioning among 90 participants (schizophrenia, bipolar disorder, and a control group). Frontal lobe functioning was assessed using Tower of London, N‐Back test, and triads test. Mean comparisons revealed significantly higher impairment in TB PM in comparison to EB PM in both the clinical groups. Significant relationship between PM and frontal lobe impairment was found. Relationship between PM and frontal lobe deficits in the clinical groups emphasises the need to include its assessment at an early stage and to develop PM rehabilitation strategies to improve the quality of living.     

One country,two cultures: Implicit space–time mappings in Southern and Northern Vietnamese

What determines how people implicitly associate the “past” and “future” with “front” and “back”? According to the Temporal Focus Hypothesis (TFH), people's cultural attitudes toward time influence their implicit space–time mappings. However, previous research mainly used cross‐cultural comparison in which the cultures compared differ not only in attentional focus on temporal events, but may also differ in other cultural values. Thus, the specific role of cultural attitudes toward time has not been tested. In the current study, we compared Southern and Northern Vietnamese who have many aspects in common but demonstrate cultural differences in attitudes toward the past and future. The results showed that the two groups of participants tended to think about time according to their temporal focus. Taken together, this pattern of results showed that within‐cultural differences in temporal focus can also predict variation in space–time mappings, which provides further supporting evidence for the TFH.     

Wednesday's Meeting Really Is on Friday: A Meta‐Analysis and Evaluation of Ambiguous Spatiotemporal Language

Experimental work has shown that spatial experiences influence spatiotemporal metaphor use. In these studies, participants are asked a question that yields different responses depending on the metaphor participants use. It has been claimed that English speakers are equally likely to respond with either variant in the absence of priming. Related studies testing non‐spatial experiences demonstrate varied results with a wide range of primes. Here, the effects of eye movement and stimuli presentation modality on comprehension of this question are investigated in different formats. In addition, the results of prior reported controls are re‐analyzed in a meta‐analysis to verify reliable ambiguity of the test question. Results suggest that English speakers have a baseline preference for the Moving Ego metaphor variant, with a stronger preference in verbal rather than written presentation. The findings have implications both for (re)interpretation of prior studies' results and future study designs.     

Temporal focus,temporal distance,and mind-wandering valence: Results from an experience sampling and an experimental study

When mind-wandering, people may think about events that happened in the past, or events that may happen in the future. Using experience sampling, we first aimed to replicate the finding that future-oriented thoughts show a greater positivity bias than past-oriented thoughts. Furthermore, we investigated whether there is a relation between the temporal distance of past- and future-oriented thoughts and the frequency of positive thoughts, a factor that has received little attention in previous work. Second, we experimentally investigated the relation between temporal focus, temporal distance, and thought valence. Both studies showed that future-oriented thoughts were more positive compared to past-oriented thoughts. Regarding temporal distance, thoughts about the distant past and future were more positive than thoughts about the near past and future in the experiment. However, the experience sampling study did not provide clear insight into this relation. Potential theoretical and methodological explanations for these findings are discussed.     

Exploring Temporal Progression of Events Using Eye Tracking

This study investigates the representation of the temporal progression of events by means of the causal change in a patient. Subjects were asked to verify the relationship between adjectives denoting a source and resulting feature of a patient. The features were presented either chronologically or inversely to a primed event context given by a verb (to cut: long–short vs. short–long). Effects on response time and on eye movement data show that the relationship between features presented chronologically is verified more easily than that between features presented inversely. Post hoc, however, we found that the effects of temporal order occurred only when subjects read the features more than once. Then, the relationship between the features is matched with the causal change implied by the event context (contextual strategy). When subjects read the features only once, subjects respond to the relationship between the features without taking into account the event context.     

Temporal generalization gradients following an interdimensional discrimination protocol

We investigated the effects of interdimensional discrimination training in the temporal generalization gradient. In a matching-to-sample task, pigeons learned to choose key S after a T–s houselight sample and key NS in the absence of the houselight sample. For one group of pigeons, T?=?20?s; for another, T?=?10?s. Subsequently, houselight duration was varied to obtain temporal generalization gradients. Results showed that (a) proportion S increased as houselight duration ranged from 0?s to T?s and then remained high for houselight durations longer than T; (b) the gradients were well described by negative-exponential functions; (c) these non-flat gradients were present from the beginning of testing, and; (d) the average gradients obtained with T?=?20?s and T?=?10?s overlapped when plotted in relative time. We conclude that temporal control does not require explicit discrimination training along the temporal dimension, and that temporal generalization gradients obtained with an interdimensional protocol show the scalar property of timing. We discuss how these findings challenge current models of timing.     

‘Language of the past’ – Exploring past tense disruption during autobiographical narration in neurodegenerative disorders

Compromised retrieval of autobiographical memory (ABM) is well established in neurodegenerative disorders. The recounting of autobiographical events is inextricably linked to linguistic knowledge, yet no study to date has investigated whether tense use during autobiographical narration is disrupted in dementia syndromes. This study investigated the incidence of correct past tense use during ABM narration in patients with Alzheimer's disease (AD, n = 10) and semantic dementia (SD, n = 10) in comparison with healthy older Controls (n = 10). Autobiographical narratives were analysed for episodic content (internal/external) and classified according to tense use (past/present). Across both patient groups, use of the past tense was significantly compromised relative to Controls, with increased levels of off‐target present tense verbs observed. Voxel‐based morphometry analyses based on structural MRI revealed differential associations between past tense use and regions of grey matter intensity in the brain. Bilateral temporal cortices were implicated in the SD group, whereas frontal, lateral, and medial temporal regions including the right hippocampus emerged in AD. This preliminary study provides the first demonstration of the disruption of specific linguistic constructs during autobiographical narration in AD and SD. Future studies are warranted to clarify at what point in the disease trajectory such deficits in tense use emerge, and whether these deficits are a product or contributing factor in memory disruption in these syndromes.     

Pure word deafness and the bilateral processing of the speech code

The analysis of pure word deafness (PWD) suggests that speech perception, construed as the integration of acoustic information to yield representations that enter into the linguistic computational system, (i) is separable in a modular sense from other aspects of auditory cognition and (ii) is mediated by the posterior superior temporal cortex in both hemispheres. PWD data are consistent with neuropsychological and neuroimaging evidence in a manner that suggests that the speech code is analyzed bilaterally. The typical lateralization associated with language processing is a property of the computational system that acts beyond the analysis of the input signal. The hypothesis of the bilateral mediation of the speech code does not imply that both sides execute the same computation. It is proposed that the speech signal is asymmetrically analyzed in the time domain, with left‐hemisphere mechanisms preferentially extracting information over shorter (25–50 ms) temporal integration windows and right mechanisms over longer (150–250 ms) windows.     

Role of left posterior superior temporal gyrus in phonological processing for speech perception and production

Models of both speech perception and speech production typically postulate a processing level that involves some form of phonological processing. There is disagreement, however, on the question of whether there are separate phonological systems for speech input versus speech output. We review a range of neuroscientific data that indicate that input and output phonological systems partially overlap. An important anatomical site of overlap appears to be the left posterior superior temporal gyrus. We then present the results of a new event-related functional magnetic resonance imaging (fMRI) experiment in which participants were asked to listen to and then (covertly) produce speech. In each participant, we found two regions in the left posterior superior temporal gyrus that responded both to the perception and production components of the task, suggesting that there is overlap in the neural systems that participate in phonological aspects of speech perception and speech production. The implications for neural models of verbal working memory are also discussed in connection with our findings.