Visual search in Alzheimer’s disease: a deficiency in processing conjunctions of features

@article{Tales2002VisualSI,
  title={Visual search in Alzheimer’s disease: a deficiency in processing conjunctions of features},
  author={Andrea Tales and Stuart R. Butler and John M. Fossey and Iain D. Gilchrist and R. W Jones and Tom Troscianko},
  journal={Neuropsychologia},
  year={2002},
  volume={40},
  pages={1849-1857}
}
Human vision often needs to encode multiple characteristics of many elements of the visual field, for example their lightness and orientation. The paradigm of visual search allows a quantitative assessment of the function of the underlying mechanisms. It measures the ability to detect a target element among a set of distractor elements. We asked whether Alzheimer's disease (AD) patients are particularly affected in one type of search, where the target is defined by a conjunction of features… Expand
New insights into feature and conjunction search: II. Evidence from Alzheimer's disease
TLDR
Pupil dilation in the AD group was greater during performance of the conjunction than the feature search tasks, although pupil response was indistinguishable for the three tasks in healthy controls, indicating an AD-specific deficit impacting upon the ability to combine information on multiple dimensions. Expand
The effects of saliency and task difficulty on visual search performance in ageing and Alzheimer’s disease
TLDR
It is concluded that inefficiency in visual search tasks in AD probably represents the product of both attention shifting and target processing factors. Expand
Visual Search Efficiency in Mild Cognitive Impairment and Alzheimer's Disease: An Eye Movement Study.
TLDR
Results showed that eye movement metrics are useful for identifying visual search impairments in MCI and AD, with possible implications in the early identification of individuals with high-risk of developing AD. Expand
Visual search patterns in semantic dementia show paradoxical facilitation of binding processes
TLDR
Performance on a visual search paradigm that includes both feature and conjunction search, while simultaneously monitoring saccadic eye movements suggests that visual talent in SD may be facilitated by more efficient visual search under distracting conditions due to enhanced function in the dorsal frontoparietal attention network. Expand
Visual Search in Alzheimer's Disease - fMRI Study
TLDR
The results imply that the mechanisms controlling spatial shifts of attention are impaired in Alzheimer’s disease patients, particularly in AD patients. Expand
Visual search in Dementia with Lewy Bodies and Alzheimer's disease
TLDR
Results suggest that the single-feature search "pop-out" effect is preserved in DLB and AD patients, whereas ability to perform the feature-conjunction search is impaired, consistent with a deficit in feature binding that may be mediated by abnormalities in networks involving the dorsal occipito-parietal cortex. Expand
Visual search in mild cognitive impairment: a longitudinal study.
TLDR
Results from the longitudinal aspect of this study illustrate how heterogeneity in the performance of brain operations other than memory in aMCI may help to inform the likelihood of their developing dementia, as those patients who were diagnosed with dementia within 2.5 years of baseline measurement showed significantly poorer visual search performance compared to those who did not. Expand
Alzheimer's Disease, Visual Search, and Instrumental Activities of Daily Living: A Review and a New Perspective on Attention and Eye Movements.
TLDR
Why analysis of patients' oculomotor behavior is promising to improve understanding of the specific search deficits in AD is considered, and why paradigms developed in research on real-world scenes and real settings in healthy individuals are valuable to investigate visual search in AD. Expand
Visual attention deficits in Alzheimer's disease: an fMRI study
TLDR
The results indicate that attention deficits in AD patients may be attributed to both binding problem and grouping inefficiency. Expand
The Multiple Features Target Cancellation (MFTC): an attentional visual conjunction search test. Normative values for the Italian population
TLDR
The MFTC task represents a useful tool that explores attentional disorders (and in particular conjunction search disturbances) and that could be helpful both in discriminating different forms of dementia and to detect mild cognitive impairment patients at risk of conversion to dementia. Expand
...
1
2
3
4
5
...

References

SHOWING 1-10 OF 54 REFERENCES
Visual Search for Feature and Conjunction Targets with an Attention Deficit
TLDR
Brain-damaged subjects who had previously been identified as suffering from a visual attention deficit for contralesional stimulation were tested on a series of visual search tasks and showed a marked deficit in conjunction search. Expand
Visual attention deficits in Alzheimer's disease: simple versus conjoined feature search.
TLDR
The authors investigated selective attention in patients with Alzheimer's disease (AD), using a well-known visual search procedure, and observed a cognitive deficit in conjunction search that was more profound than that predicted on the basis of previous reports of global cognitive slowing in AD. Expand
Guided Search 2.0 A revised model of visual search
  • J. Wolfe
  • Psychology, Medicine
  • Psychonomic bulletin & review
  • 1994
TLDR
This paper reviews the visual search literature and presents a model of human search behavior, a revision of the guided search 2.0 model in which virtually all aspects of the model have been made more explicit and/or revised in light of new data. Expand
Selective impairment of spatial attention during visual search in Alzheimer's disease
TLDR
Pathology affecting the association parietal and extrastriate areas may mediate impairment of spatial attention and visual search in AD. Expand
Alzheimer disease constricts the dynamic range of spatial attention in visual search
TLDR
The cue size effect was evident in both feature and conjunction search, but was greatly reduced in both old-old and DAT groups compared to the young-old, and the dynamic range of spatial attention was restricted to the most precise cue in the DAT group. Expand
Attention Mechanisms in Visual SearchAn fMRI Study
TLDR
Using functional magnetic resonance imaging (fMRI), it is shown that the cerebral networks involved in efficient and inefficient search overlap almost completely, and it is likely that visual search does not require serial processing, otherwise the existence of a serial searchlight that operates in the extrastriate cortex but differs from the visuospatial shifts of attention involving the parietal and frontal regions is assumed. Expand
Controlling the focus of spatial attention during visual search: effects of advanced aging and Alzheimer disease.
TLDR
The results indicate that both Alzheimer's disease and, to a lesser degree, advanced aging, reduce control of the spatial focus of attention. Expand
Spatial- and object-based attentional deficits in Alzheimer's disease. Relationship to HMPAO-SPECT measures of parietal perfusion.
TLDR
Results provide evidence for the specialized roles of the right and left parietal regions in the spatial and object components of attentional shifting respectively, and suggest that the cognitive profile associated with Alzheimer's disease includes both spatial- and object-based attentional impairments. Expand
Vision and cognition in Alzheimer’s disease
TLDR
The findings show that AD affects several aspects of vision and are compatible with the hypothesis that visual dysfunction in AD may contribute to performance decrements in other cognitive domains. Expand
Visuospatial attention in dementia of the Alzheimer type.
TLDR
Intact focusing and impaired disengagement of visuospatial attention may be linked to dysfunction in early DAT of cortico-cortical networks linking the posterior parietal and frontal lobes. Expand
...
1
2
3
4
5
...