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  1. Article ; Online: A presaccadic perceptual impairment at the postsaccadic location of the blindspot.

    Smith, Daniel T / Beierholm, Ulrik / Avery, Mark

    PloS one

    2023  Volume 18, Issue 9, Page(s) e0291582

    Abstract: Saccadic eye movements are preceded by profound changes in visual perception. These changes have been linked to the phenomenon of 'forward remapping', in which cells begin to respond to stimuli that appear in their post-saccadic receptive field before ... ...

    Abstract Saccadic eye movements are preceded by profound changes in visual perception. These changes have been linked to the phenomenon of 'forward remapping', in which cells begin to respond to stimuli that appear in their post-saccadic receptive field before the eye has moved. Few studies have examined the perceptual consequences of remapping of areas of impaired sensory acuity, such as the blindspot. Understanding the perceptual consequences of remapping of scotomas may produce important insights into why some neurovisual deficits, such as hemianopia are so intractable for rehabilitation. The current study took advantage of a naturally occurring scotoma in healthy participants (the blindspot) to examine pre-saccadic perception at the upcoming location of the blindspot. Participants viewed stimuli monocularly and were required to make stimulus-driven vertical eye-movements. At a variable latency between the onset of saccade target (ST) and saccade execution a discrimination target (DT) was presented at one of 4 possible locations; within the blindspot, contralateral to the blindspot, in post-saccadic location of the blindspot and contralateral to the post-saccadic location of the blindspot. There was a significant perceptual impairment at the post-saccadic location of the blindspot relative to the contralateral post-saccadic location of the blindspot and the post-saccadic location of the blindspot in a no-saccade control condition. These data are consistent with the idea that the visual system includes a representation of the blindspot which is remapped prior to saccade onset.
    MeSH term(s) Humans ; Eye Movements ; Saccades ; Healthy Volunteers ; Hemianopsia ; Hypesthesia ; Scotoma
    Language English
    Publishing date 2023-09-14
    Publishing country United States
    Document type Journal Article
    ZDB-ID 2267670-3
    ISSN 1932-6203 ; 1932-6203
    ISSN (online) 1932-6203
    ISSN 1932-6203
    DOI 10.1371/journal.pone.0291582
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Reduced mood variability is associated with enhanced performance during ultrarunnning.

    Burgum, Paul / Smith, Daniel T

    PloS one

    2021  Volume 16, Issue 9, Page(s) e0256888

    Abstract: Ultrarunning requires extraordinary endurance but the psychological factors involved in successful ultrarunning are not well understood. One widely held view is that fluctuations in mood play a pivotal role in performance during endurance events. However, ...

    Abstract Ultrarunning requires extraordinary endurance but the psychological factors involved in successful ultrarunning are not well understood. One widely held view is that fluctuations in mood play a pivotal role in performance during endurance events. However, this view is primarily based on comparisons of mood before and after marathons and shorter running events. Indeed, to date no study has explicitly examined mood changes during a competive ultramarathon. To address this issue, we measured mood fluctuations in athletes competing in the Hardmoors 60, a 100 km, single day continuous trail-ultramarathon, and examined how variation in mood related to performance, as measured by completion time. The key finding was that the variability of athletes Total Mood Disturbance (TMD) score was significantly and positively correlated with completion time, consistent with the idea that mood is an important factor in determining race performance. Athletes also experienced a significant increase in tension immediately prior to race onset. This effect was more pronounced in less experienced athletes and significantly attenuated by measurement stage 1 at 35.4 km, which suggests the effect was driven by the release of pre-competition anxiety. Depression, anger and TMD were significantly lower at the pre-race measurement compared to the baseline measurement taken the week before. Consistent with previous studies, there were also significant increases in fatigue, anger and TMD during the race. The data are interpreted in terms of the Psychobiological model of endurance and may have broader implications for the understanding of endurance performance in other domains.
    MeSH term(s) Adult ; Affect ; Affective Symptoms/psychology ; Athletes/psychology ; Fatigue/psychology ; Female ; Humans ; Male ; Marathon Running/psychology ; Middle Aged ; Physical Endurance
    Language English
    Publishing date 2021-09-16
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2267670-3
    ISSN 1932-6203 ; 1932-6203
    ISSN (online) 1932-6203
    ISSN 1932-6203
    DOI 10.1371/journal.pone.0256888
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Precision in spatial working memory examined with mouse pointing.

    McAteer, Siobhan M / McGregor, Anthony / Smith, Daniel T

    Vision research

    2023  Volume 215, Page(s) 108343

    Abstract: The capacity of visuospatial working memory (VSWM) is limited. However, there is continued debate surrounding the nature of this capacity limitation. The resource model (Bays et al., 2009) proposes that VSWM capacity is limited by the precision with ... ...

    Abstract The capacity of visuospatial working memory (VSWM) is limited. However, there is continued debate surrounding the nature of this capacity limitation. The resource model (Bays et al., 2009) proposes that VSWM capacity is limited by the precision with which visuospatial features can be retained. In one of the few studies of spatial working memory, Schneegans and Bays (2016) report that memory guided pointing responses show a monotonic decrease in precision as set size increases, consistent with resource models. Here we report two conceptual replications of this study that use mouse responses rather than pointing responses. Overall results are consistent with the resource model, as there was an exponential increase in localisation error and monotonic increases in the probability of misbinding and guessing with increases in set size. However, an unexpected result of Experiment One was that, unlike Schneegans and Bays (2016), imprecision did not increase between set sizes of 2 and 8. Experiment Two replicated this effect and ruled out the possibility that the invariance of imprecision at set sizes greater than 2 was a product of oculomotor strategies during recall. We speculate that differences in imprecision are related to additional visuomotor transformations required for memory-guided mouse localisation compared to memory-guided manual pointing localisation. These data demonstrate the importance of considering the nature of the response modality when interpreting VSWM data.
    MeSH term(s) Animals ; Mice ; Memory, Short-Term/physiology ; Mental Recall/physiology ; Spatial Memory
    Language English
    Publishing date 2023-12-30
    Publishing country England
    Document type Journal Article
    ZDB-ID 200427-6
    ISSN 1878-5646 ; 0042-6989
    ISSN (online) 1878-5646
    ISSN 0042-6989
    DOI 10.1016/j.visres.2023.108343
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Factors associated with declaration of disability in medical students and junior doctors, and the association of declared disability with academic performance: observational study using data from the UK Medical Education Database, 2002-2018 (UKMED54).

    Murphy, Michael J / Dowell, Jon S / Smith, Daniel T

    BMJ open

    2022  Volume 12, Issue 4, Page(s) e059179

    Abstract: Objectives: To examine factors associated with declaration of disability by medical students and doctors, and the association of declared disability with academic performance.: Design: Observational study using record-linked data collected between ... ...

    Abstract Objectives: To examine factors associated with declaration of disability by medical students and doctors, and the association of declared disability with academic performance.
    Design: Observational study using record-linked data collected between 2002 and 2018.
    Setting: UK Medical Education Database is a repository of data relating to training of medical students and doctors. Disability and other data are record-linked.
    Participants: All students starting at a UK medical school between 2002 and 2018 (n=135 930).
    Main outcome measures: Declared disability was categorised by the Higher Education Statistics Authority. Outcomes related to undergraduate academic performance included scores in the educational performance measure (EPM), prescribing safety assessment and situational judgement test. Performance in postgraduate examinations was studied, as well as prior attainment in school examinations and aptitude tests.
    Results: Specific learning disability (SLD) was the most commonly declared disability (3.5% compared with the next most commonly declared disability at 1.0% of n=129 345 all cases in the study), and during the period covered by the data, SLD declarations increased from 1.4% (n=6440 for students starting in 2002) to 4.6% (n=8625 for students starting in 2018). In a logistic regression, the following factors predicted recording of SLD on entry to medical school ((exp(B)±95% CI), p<0.0001 unless otherwise stated): attendance at a fee-paying school (2.306±0.178), graduate status (1.806±0.205), participation of local areas quintile (1.089±0.030), age (1.034±0.012). First year medical students were less likely to declare SLD if they were from a non-white ethnic background (Asian/Asian British 0.324±0.034, black/black British 0.571±0.102, mixed 0.731±0.108, other ethnic groups 0.566±0.120), female (0.913±0.059; p=0.007) or from a low index of multiple deprivation quintile (0.963±0.029); p=0.017. In univariate analysis with Bonferroni corrections applied for multiple tests, no significant difference was observed in the recording of SLD according to socioeconomic class (χ
    Conclusions: Substantial increases in declaration of SLD may reflect changes in the social and legal environment during the period of the study. Those who declare SLD are just as likely to gain a primary medical qualification as those who do not. For some individuals, disability declaration appears to depend on context, based on differences in numbers declaring SLD before, during and after medical school.
    MeSH term(s) Aptitude Tests ; Education, Medical ; Female ; Humans ; Schools, Medical ; Students, Medical ; United Kingdom/epidemiology
    Language English
    Publishing date 2022-03-31
    Publishing country England
    Document type Journal Article ; Observational Study
    ZDB-ID 2599832-8
    ISSN 2044-6055 ; 2044-6055
    ISSN (online) 2044-6055
    ISSN 2044-6055
    DOI 10.1136/bmjopen-2021-059179
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: On the link between attentional search and the oculomotor system: Is preattentive search restricted to the range of eye movements?

    Casteau, Soazig / Smith, Daniel T

    Attention, perception & psychophysics

    2020  Volume 82, Issue 2, Page(s) 518–532

    Abstract: It has been proposed that covert visual search can be fast, efficient, and stimulus driven, particularly when the target is defined by a salient single feature, or slow, inefficient, and effortful when the target is defined by a nonsalient conjunction of ...

    Abstract It has been proposed that covert visual search can be fast, efficient, and stimulus driven, particularly when the target is defined by a salient single feature, or slow, inefficient, and effortful when the target is defined by a nonsalient conjunction of features. This distinction between fast, stimulus-driven orienting and slow, effortful orienting can be related to the distinction between exogenous spatial attention and endogenous spatial attention. Several studies have shown that exogenous, covert orienting is limited to the range of saccadic eye movements, whereas covert endogenous orienting is independent of the range of saccadic eye movements. The current study examined whether covert visual search is affected in a similar way. Experiment 1 showed that covert visual search for feature singletons was impaired when stimuli were presented beyond the range of saccadic eye movements, whereas conjunction search was unaffected by array position. Experiment 2 replicated and extended this effect by measuring search times at 6 eccentricities. The impairment in covert feature search emerged only when stimuli crossed the effective oculomotor range and remained stable for locations further into the periphery, ruling out the possibility that the results of Experiment 1 were due to a failure to fully compensate for the effects of cortical magnification. The findings are interpreted in terms of biased competition and oculomotor theories of spatial attention. It is concluded that, as with covert exogenous orienting, biological constraints on overt orienting in the oculomotor system constrain covert, preattentive search.
    MeSH term(s) Adult ; Attention/physiology ; Eye Movements/physiology ; Female ; Humans ; Male ; Orientation/physiology ; Photic Stimulation/methods ; Random Allocation ; Reaction Time/physiology ; Saccades/physiology ; Young Adult
    Language English
    Publishing date 2020-01-15
    Publishing country United States
    Document type Journal Article
    ZDB-ID 2464550-3
    ISSN 1943-393X ; 1943-3921
    ISSN (online) 1943-393X
    ISSN 1943-3921
    DOI 10.3758/s13414-019-01949-4
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Scaling up high-throughput phenotyping for abiotic stress selection in the field.

    Smith, Daniel T / Potgieter, Andries B / Chapman, Scott C

    TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik

    2021  Volume 134, Issue 6, Page(s) 1845–1866

    Abstract: Key message: High-throughput phenotyping (HTP) is in its infancy for deployment in large-scale breeding programmes. With the ability to measure correlated traits associated with physiological ideotypes, in-field phenotyping methods are available for ... ...

    Abstract Key message: High-throughput phenotyping (HTP) is in its infancy for deployment in large-scale breeding programmes. With the ability to measure correlated traits associated with physiological ideotypes, in-field phenotyping methods are available for screening of abiotic stress responses. As cropping environments become more hostile and unpredictable due to the effects of climate change, the need to characterise variability across spatial and temporal scales will become increasingly important. The sensor technologies that have enabled HTP from macroscopic through to satellite sensors may also be utilised here to complement spatial characterisation using envirotyping, which can improve estimations of genotypic performance across environments by better accounting for variation at the plot, trial and inter-trial levels. Climate change is leading to increased variation at all physical and temporal scales in the cropping environment. Maintaining yield stability under circumstances with greater levels of abiotic stress while capitalising upon yield potential in good years, requires approaches to plant breeding that target the physiological limitations to crop performance in specific environments. This requires dynamic modelling of conditions within target populations of environments, GxExM predictions, clustering of environments so breeding trajectories can be defined, and the development of screens that enable selection for genetic gain to occur. High-throughput phenotyping (HTP), combined with related technologies used for envirotyping, can help to address these challenges. Non-destructive analysis of the morphological, biochemical and physiological qualities of plant canopies using HTP has great potential to complement whole-genome selection, which is becoming increasingly common in breeding programmes. A range of novel analytic techniques, such as machine learning and deep learning, combined with a widening range of sensors, allow rapid assessment of large breeding populations that are repeatable and objective. Secondary traits underlying radiation use efficiency and water use efficiency can be screened with HTP for selection at the early stages of a breeding programme. HTP and envirotyping technologies can also characterise spatial variability at trial and within-plot levels, which can be used to correct for spatial variations that confound measurements of genotypic values. This review explores HTP for abiotic stress selection through a physiological trait lens and additionally investigates the use of envirotyping and EC to characterise spatial variability at all physical scales in METs.
    MeSH term(s) Climate Change ; Crops, Agricultural/genetics ; Genotype ; Models, Genetic ; Phenotype ; Plant Breeding ; Selection, Genetic ; Stress, Physiological
    Language English
    Publishing date 2021-06-02
    Publishing country Germany
    Document type Journal Article ; Review
    ZDB-ID 2170-2
    ISSN 1432-2242 ; 0040-5752
    ISSN (online) 1432-2242
    ISSN 0040-5752
    DOI 10.1007/s00122-021-03864-5
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  7. Article ; Online: Spatial attention and spatial short term memory in PSP and Parkinson's disease.

    Smith, Daniel T / Casteau, Soazig / Archibald, Neil

    Cortex; a journal devoted to the study of the nervous system and behavior

    2021  Volume 137, Page(s) 49–60

    Abstract: Progressive Supranuclear Palsy (PSP) is a neurodegenerative disorder characterised by deterioration in motor, oculomotor and cognitive function. A key clinical feature of PSP is the progressive paralysis of eye movements, most notably for vertical ... ...

    Abstract Progressive Supranuclear Palsy (PSP) is a neurodegenerative disorder characterised by deterioration in motor, oculomotor and cognitive function. A key clinical feature of PSP is the progressive paralysis of eye movements, most notably for vertical saccades. These oculomotor signs can be subtle, however, and PSP is often misdiagnosed as Parkinson's disease (PD), in its early stages. Although some of the clinical features of PD and PSP overlap, they are distinct disorders with differing underlying pathological processes, responses to treatment and prognoses. One key difference lies in the effects the diseases have on cognition. The oculomotor system is tightly linked to cognitive processes such as spatial attention and spatial short-term memory (sSTM), and previous studies have suggested that PSP and PD experience different deficits in these domains. We therefore hypothesised that people with PSP (N = 15) would experience problems with attention (assessed with feature and conjunction visual search tasks) and sSTM (assessed with the Corsi blocks task) compared to people with PD (N = 16) and Age Matched Controls (N = 15). As predicted, feature and conjunction search were sgnificantly slower in the PSP group compared to the other groups, and this deficit was significantly worse for feature compared to conjunction search. The PD group did not differ from AMC on feature search but were significantly impaired on the conjunction search. The PSP group also had a pronounced vertical sSTM impairment that was not present in PD or AMC groups. It is argued that PSP is associated with specific impairment of visuospatial cognition which is caused by degeneration of the oculomotor structures that support exogenous spatial attention, consistent with oculomotor theories of spatial attention and memory.
    MeSH term(s) Attention ; Cognition ; Humans ; Memory, Short-Term ; Parkinson Disease ; Supranuclear Palsy, Progressive
    Language English
    Publishing date 2021-01-22
    Publishing country Italy
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 280622-8
    ISSN 1973-8102 ; 0010-9452
    ISSN (online) 1973-8102
    ISSN 0010-9452
    DOI 10.1016/j.cortex.2020.12.019
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  8. Article ; Online: Gaze cueing, mental States, and the effect of autistic traits.

    Morgan, Emma J / Smith, Daniel T / Freeth, Megan

    Attention, perception & psychophysics

    2021  Volume 85, Issue 2, Page(s) 485–493

    Abstract: The ability to interpret and follow the gaze of our social partners is an integral skill in human communication. Recent research has demonstrated that gaze following behaviour is influenced by theory of mind (ToM) processes. However, it has yet to be ... ...

    Abstract The ability to interpret and follow the gaze of our social partners is an integral skill in human communication. Recent research has demonstrated that gaze following behaviour is influenced by theory of mind (ToM) processes. However, it has yet to be determined whether the modulation of gaze cueing by ToM is affected by individual differences, such as autistic traits. The aim of this experiment was to establish whether autistic traits in neurotypical populations affect the mediation of gaze cueing by ToM processes. This study used a gaze cueing paradigm within a change detection task. Participants' perception of a gaze cue was manipulated such that they only believed the cue to be able to 'see' in one condition. The results revealed that participants in the Low Autistic Traits group were significantly influenced by the mental state of the gaze cue and were more accurate on valid trials when they believed the cue could 'see'. By contrast, participants in the High Autistic Traits group were also more accurate on valid trials, but this was not influenced by the mental state of the gaze cue. This study therefore provides evidence that autistic traits influence the extent to which mental state attributions modulate social attention in neurotypical adults.
    MeSH term(s) Adult ; Humans ; Cues ; Fixation, Ocular ; Autistic Disorder ; Attention ; Social Perception
    Language English
    Publishing date 2021-09-14
    Publishing country United States
    Document type Journal Article
    ZDB-ID 2464550-3
    ISSN 1943-393X ; 1943-3921
    ISSN (online) 1943-393X
    ISSN 1943-3921
    DOI 10.3758/s13414-021-02368-0
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: Oculomotor rehearsal in visuospatial working memory.

    McAteer, Siobhan M / McGregor, Anthony / Smith, Daniel T

    Attention, perception & psychophysics

    2022  

    Abstract: The neural and cognitive mechanisms of spatial working memory are tightly coupled with the systems that control eye movements, but the precise nature of this coupling is not well understood. It has been argued that the oculomotor system is selectively ... ...

    Abstract The neural and cognitive mechanisms of spatial working memory are tightly coupled with the systems that control eye movements, but the precise nature of this coupling is not well understood. It has been argued that the oculomotor system is selectively involved in rehearsal of spatial but not visual material in visuospatial working memory. However, few studies have directly compared the effect of saccadic interference on visual and spatial memory, and there is little consensus on how the underlying working memory representation is affected by saccadic interference. In this study we aimed to examine how working memory for visual and spatial features is affected by overt and covert attentional interference across two experiments. Participants were shown a memory array, then asked to either maintain fixation or to overtly or covertly shift attention in a detection task during the delay period. Using the continuous report task we directly examined the precision of visual and spatial working memory representations and fit psychophysical functions to investigate the sources of recall error associated with different types of interference. These data were interpreted in terms of embodied theories of attention and memory and provide new insights into the nature of the interactions between cognitive and motor systems.
    Language English
    Publishing date 2022-11-22
    Publishing country United States
    Document type Journal Article
    ZDB-ID 2464550-3
    ISSN 1943-393X ; 1943-3921
    ISSN (online) 1943-393X
    ISSN 1943-3921
    DOI 10.3758/s13414-022-02601-4
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: Dynamic resource allocation in spatial working memory during full and partial report tasks.

    McAteer, Siobhan M / Ablott, Emma / McGregor, Anthony / Smith, Daniel T

    Journal of vision

    2023  Volume 23, Issue 2, Page(s) 10

    Abstract: Serial position effects are well-documented in working memory literature. Studies of spatial short-term memory that rely on binary response; full report tasks tend to report stronger primacy than recency effects. In contrast, studies that utilize a ... ...

    Abstract Serial position effects are well-documented in working memory literature. Studies of spatial short-term memory that rely on binary response; full report tasks tend to report stronger primacy than recency effects. In contrast, studies that utilize a continuous response, partial report task report stronger recency than primacy effects (Gorgoraptis, Catalao, Bays, & Husain, 2011; Zokaei, Gorgoraptis, Bahrami, Bays, & Husain, 2011). The current study explored the idea that probing spatial working memory using full and partial continuous response tasks would produce different distributions of visuospatial working memory resources across spatial sequences and, therefore, explain the conflicting results in the literature. Experiment 1 demonstrated that primacy effects were observed when memory was probed with a full report task. Experiment 2 confirmed this finding while controlling eye movements. Critically, Experiment 3 demonstrated that switching from a full to a partial report task abolished the primacy effect and produced a recency effect, consistent with the idea that the distribution of resources in visuospatial working memory depends on the type of recall required. It is argued that the primacy effect in the whole report task arose from the accumulation of noise caused by the execution of multiple spatially directed actions during recall, whereas the recency effect in the partial report task reflects the redistribution of preallocated resources when an anticipated item is not presented. These data show that it is possible to reconcile apparently contradictory findings within the resource theory of spatial working memory and the importance of considering how memory is probed when interpreting behavioral data through the lens of resource theories of spatial working memory.
    MeSH term(s) Humans ; Memory, Short-Term/physiology ; Mental Recall/physiology ; Spatial Memory ; Eye Movements
    Language English
    Publishing date 2023-02-19
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2106064-2
    ISSN 1534-7362 ; 1534-7362
    ISSN (online) 1534-7362
    ISSN 1534-7362
    DOI 10.1167/jov.23.2.10
    Database MEDical Literature Analysis and Retrieval System OnLINE

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