The temporal–hippocampal region and retention: The role of temporo-entorhinal connections in rats

Results from previous studies suggest that the entorhinal cortex may be involved in mnemonic processes. The present study was carried out to investigate whether disruption of fibre connections between the temporal cortex and lateral entorhinal area may impair retention of a pre-operatively acquired simultaneous brightness discrimination task. The lesion resulted in a severe impairment in retaining the discrimination task (Experiment 1). The retention deficit could not be traced into the hippocampal formation by making perforant path lesions or hippocampal lesions (Experiment 2). The results indicate that the lateral entorhinal cortex is more crucial for reference memory than the hippocampal formation.     

Dreaming and cognition in patients with frontotemporal dysfunction

Individuals with Parkinson’s disease (PD) and temporal lobe epilepsy (TLE) have hallucinations and mild cognitive dysfunction. The objective of this work was to study dreams in PD and TLE patients using a common functional model of dream production involving the limbic and paralimbic structures.Dreams were characterised in early-stage PD (19 males) and TLE patients (52) with dream diaries classified by the Hall van de Castle system and were compared with matched controls.In PD, there were significant differences between patients’ dreams and those of controls: animals, physical aggression, and a befriender were more common in patients, and aggressor and bodily misfortunes were less common. The dreams of patients with frontal dysfunction showed more aggressive features.TLE patients had lower recall than PD patients and a higher proportion of dreams involving family and familiar settings, lower proportions involving success, and a higher incidence of frontal dysfunction.The dreams of PD and TLE patients share important features.     

Time engineering in the schizophrenias

Temporal conceptualisation and investigation of brain-mind functioning, in health and in neuro-psychiatric disease, is a relatively new field in neuroscience. The cerebellum has long been suspected as the centre for the organization of timing in the brain. This article examines endophenotypes for temporal coding in schizophrenia, centring on aberrant, neuronal, input connectivity to the cerebellum.     

The associated nontargets effect: Evidence of nontarget processing at and beyond the level of letter recognition

In four visual search tasks participants were asked to make a target response if either of two targets was present and to make a nontarget response if neither target was present. Some target-absent displays included only nontarget stimuli or features that never occurred in the same displays as targets, whereas other target-absent displays included nontarget stimuli or features that did sometimes occur with targets. Nontarget responses were reliably faster in the former case than in the latter. This “associated nontargets effect” indicates that nontargets are not simply classified as nontargets but in addition are discriminated from one another. Current visual search models may underestimate the degree to which nontargets are processed during search.     

The detection of temporally defined objects does not require focused attention

Perceptual grouping is crucial to distinguish objects from their background. Recent studies have shown that observers can detect an object that does not have any unique qualities other than unique temporal properties. A crucial question is whether focused attention is needed for this type of grouping. In two visual search experiments, we show that searching for an object defined by temporal grouping can occur in parallel. These findings suggest that focused attention is not needed for temporal grouping to occur. It is proposed that temporal grouping may occur because the neurons representing the changing object elements adopt firing frequencies that cause the visual system to bind these elements together without the need for focused attention.     

Modality effects in memory for basic stimulus attributes: A temporal and nontemporal comparison

Previous research suggests that there are significant differences in the operation of reference memory for stimuli of different modalities, with visual temporal entries appearing to be more durable than auditory entries (Ogden, Wearden, & Jones, 2008 Ogden, R. S., Wearden, J. H. and Jones, L. A. 2008. The remembrance of times past: Interference in temporal reference memory. Journal of Experimental Psychology: Human Perception and Performance, 34: 1524–1544. [Crossref], [PubMed], [Web of Science ®] , [Google Scholar], 2010). Ogden et al. (2008 Ogden, R. S., Wearden, J. H. and Jones, L. A. 2008. The remembrance of times past: Interference in temporal reference memory. Journal of Experimental Psychology: Human Perception and Performance, 34: 1524–1544. [Crossref], [PubMed], [Web of Science ®] , [Google Scholar], 2010 Ogden, R. S., Wearden, J. H. and Jones, L. A. 2010. Are memories for duration modality specific?. Quarterly Journal of Experimental Psychology, 63: 65–80. [Taylor & Francis Online], [Web of Science ®] , [Google Scholar]) demonstrated that when participants were required to store multiple auditory temporal standards over a period of delay there was significant systematic interference to the representation of the standard characterized by shifts in the location of peak responding. No such performance deterioration was observed when multiple visually presented durations were encoded and maintained. The current article explored whether this apparent modality-based difference in reference memory operation is unique to temporal stimuli or whether similar characteristics are also apparent when nontemporal stimuli are encoded and maintained. The modified temporal generalization method developed in Ogden et al. (2008) Ogden, R. S., Wearden, J. H. and Jones, L. A. 2008. The remembrance of times past: Interference in temporal reference memory. Journal of Experimental Psychology: Human Perception and Performance, 34: 1524–1544. [Crossref], [PubMed], [Web of Science ®] , [Google Scholar] was employed; however, standards and comparisons varied by pitch (auditory) and physical line length (visual) rather than duration. Pitch and line length generalization results indicated that increasing memory load led to more variable responding and reduced recognition of the standard; however, there was no systematic shift in the location of peak responding. Comparison of the results of this study with those of Ogden et al. (2008 Ogden, R. S., Wearden, J. H. and Jones, L. A. 2008. The remembrance of times past: Interference in temporal reference memory. Journal of Experimental Psychology: Human Perception and Performance, 34: 1524–1544. [Crossref], [PubMed], [Web of Science ®] , [Google Scholar], 2010 Ogden, R. S., Wearden, J. H. and Jones, L. A. 2010. Are memories for duration modality specific?. Quarterly Journal of Experimental Psychology, 63: 65–80. [Taylor & Francis Online], [Web of Science ®] , [Google Scholar]) suggests that although performance deterioration as a consequence of increases in memory load is common to auditory temporal and nontemporal stimuli and visual nontemporal stimuli, systematic interference is unique to auditory temporal processing.     

Temporal preparation decreases perceptual latency: Evidence from a clock paradigm

A clock paradigm was employed to assess whether temporal preparation decreases the time to detect the onset of a stimulus—that is, perceptual latency. In four experiments participants watched a revolving clock hand while listening to soft or loud target tones under high or low temporal preparation. At the end of each trial, participants reported the clock hand position at the onset of the target tone. The deviation of the reported clock hand position from the actual position indexed perceptual latency. As expected, perceptual latency decreased with target tone intensity. Most importantly, however, greater temporal preparation decreased perceptual latency in all four experiments, especially for soft tones, which supports rather directly the idea that temporal preparation diminishes the duration of perceptual processing.     

The effects of acute exercise on temporal generalization

Sixteen healthy college students performed a multiple-trial referenced temporal generalization task and an episodic temporal generalization task before and during moderate-intensity aerobic exercise. The same tasks were performed in a resting control condition. Working memory tasks were also administered before, during, and after exercise to determine whether exercise affected working memory processes. Temporal generalization gradients demonstrated leftward shifts during exercise when compared to rest, indicating that the subject perceived intervals to elapse more slowly. This finding is consistent with an increased pacemaker speed. Subjective lengthening of stimuli as the task progressed did not occur during exercise or rest. No significant differences were observed on the episodic timing task, nor were any differences found on the working memory tasks. These findings provide support for the notion that exercise influences the internal clock in a manner similar to other arousal-inducing manipulations.     

The effect of scene structure on time perception

The current experiments examined the hypothesis that scene structure affects time perception. In three experiments, participants judged the duration of realistic scenes that were presented in a normal or jumbled (i.e., incoherent) format. Experiment 1 demonstrated that the subjective duration of normal scenes was greater than subjective duration of jumbled scenes. In Experiment 2, gridlines were added to both normal and jumbled scenes to control for the number of line terminators, and scene structure had no effect. In Experiment 3, participants performed a secondary task that required paying attention to scene structure, and scene structure's effect on duration judgements reemerged. These findings are consistent with the idea that perceived duration can depend on visual–cognitive processing, which in turn depends on both the nature of the stimulus and the goals of the observer.     

The influence of temporal regularities on the implicit learning of pitch structures

Implicit learning is the acquisition of complex information without the intention to learn. The aim of this study was to investigate the influence of temporal regularities on the implicit learning of an artificial pitch grammar. According to the dynamic attending theory (DAT) external regularities can entrain internal oscillators that guide attention over time, inducing temporal expectations that influence perception of future events. In the present study, the presentation of the artificial pitch grammar in the exposure phase was temporally either regular or irregular for one of two participant groups. Based on the DAT, it was hypothesized that the regular temporal presentation would favour implicit learning of tone structures in comparison to the irregular temporal presentation. Results demonstrated learning of the artificial grammar for the group with the regular exposure phase and partial learning for the group with the irregular exposure phase. These findings suggest that the regular presentation helps listeners to develop perceptual expectations about the temporal occurrence of future tones and thus facilitates the learning of the artificial pitch grammar.