Geriatr Psychol Neuropsychiatr Vieil
June 2024
Younger adults have difficulties identifying emotional facial expressions from faces covered by face masks. It is important to evaluate how face mask wearing might specifically impact older people, because they have lower emotion identification performance than younger adults, even without face masks. We compared performance of 62 young and 38 older adults in an online task of emotional facial expression identification using masked or unmasked pictures of faces with fear, happiness, anger, surprise, and neutral expression, from different viewpoints.
View Article and Find Full Text PDFWord reading requires a range of spatial attention processes, such as orienting to a specific word and selecting it while ignoring other words. This study investigated whether deficits of these spatial attention processes can show dissociations after hemispheric lesions. Thirty-nine patients with left or right focal epilepsy and 66 healthy participants had to read aloud four-letter words presented in the left and right visual hemifields.
View Article and Find Full Text PDFGeriatr Psychol Neuropsychiatr Vieil
October 2021
Attention deficits are encountered at a very early stage in the development of Alzheimer's disease. While these deficits may be detected using classic clinical tests or even through simple observation, experimental tools enable a more precise evaluation of these deficits, typically by differentiating between conditions in which the quantity of attention needed varies, and by recording response times, which allows for a more precise and modulated measurement. The sensitivity of these tools can be further increased by analysing the intra-individual variability of performance in these experiments, which is particularly significant during the earliest stages of the disease.
View Article and Find Full Text PDFGeriatr Psychol Neuropsychiatr Vieil
December 2020
Attention deficits are encountered very early in the development of Alzheimer's disease. While these deficits may be detected using classic clinical tests or even from simple observation, experimental tools enable a more precise evaluation of these deficits, typically by subtracting between conditions which vary the quantity of necessary attention, and by recording response times which allow a more precise and modulated measurement. The sensitivity of these tools can be further increased by analyzing the intra-individual variability of performance in these experiments, this variability being particularly important during the earliest stages of the disease.
View Article and Find Full Text PDFGeriatr Psychol Neuropsychiatr Vieil
September 2019
Visual perception is humans' preferred way for taking information on the surrounding world. Visual perception is frequently impaired in patients with Alzheimer's disease, lessening patients' quality of life, and making evaluation of other cognitive deficits more complicated. Our review covers the recent literature describing visual perception deficits in patients suffering from Alzheimer's disease by classifying them according to their neuroanatomical correspondence: retina, visual pathway, subcortical structures, occipital visual cortex, occipito-temporal "what" and occipito-parietal "where" pathways.
View Article and Find Full Text PDFWord processing in left (LVF) and right (RVF) visual fields may be affected by left hemisphere activation during reading and by script direction. We evaluated the effect of script direction by presenting words in left-to-right (French) and right-to-left (Hebrew) scripts to bilingual French participants. Words of different lengths were presented in the LVF and the RVF in a naming task.
View Article and Find Full Text PDFAcquired spatial dyslexia is a reading disorder frequently occurring after left or right posterior brain lesions. This article describes several types of spatial dyslexia with an attentional approach. After right posterior lesions, patients show left neglect dyslexia with errors on the left side of text, words, and non-words.
View Article and Find Full Text PDFA written word is identified more easily when it is presented in the right than in the left visual field. This right visual field superiority (RVFS) may be explained by the left hemisphere's role in reading and by reading direction in left-to-right scripts. However, the comparison of left-to-right and right-to-left scripts had not resulted in systematic differences.
View Article and Find Full Text PDFReading a letter string requires attentional orienting toward the beginning of the string (left-dominant orientation), followed by orienting along the string. These attentional-orienting processes differ according to the lexicality of the letter string: Sequential processes apply when reading nonwords or pseudowords, while words can be processed more globally. The aim of this study was to evaluate the development of these attentional processes involved in reading.
View Article and Find Full Text PDFPreparatory attention (PA) is the ability to allocate attention to a stimulus prior to its occurrence and is a crucial component of attentional control. We investigated the role of brain hemispheres in PA using an experimental test in which normal participants responded to a target that could appear in the right or the left visual fields, thus projecting to the left or the right hemispheres, while ignoring a central distractor that could appear in the preparatory phase preceding the target. This experimental test measures the ability of participants to modulate PA directed to a target location when the probability of a distractor occurrence varies across three blocks of trials (0%, 33%, 67%).
View Article and Find Full Text PDFWords presented to the right visual field (RVF) are recognized more readily than those presented to the left visual field (LVF). Whereas the attentional bias theory proposes an explanation in terms of attentional imbalance between visual fields, the attentional advantage theory assumes that words presented to the RVF are processed automatically while LVF words need attention. In this study, we exploited coupling between attention and saccadic eye movements to orient spatial attention to one or the other visual field.
View Article and Find Full Text PDFObjective: The right visual field superiority (RVFS) for words may be explained by the cerebral lateralization for language, the scanning habits in relation to script direction, and spatial attention. The present study explored the influence of spatial attention on the RVFS in relation to scanning habits in school-age children.
Methods: French second- and fourth-graders identified briefly presented French parafoveal words.
Child Neuropsychol
January 2014
Orienting of attention was investigated in 6-, 8-, and 10-year-olds and in young adults, in a spatial cueing experiment comparing nonpredictive, predictive, and counterpredictive cues (in different blocks). A larger positive orienting effect (advantage of valid over invalid cues) in the predictive than in the nonpredictive condition occurred in all groups, showing efficient endogenous orienting of attention. However, this effect was larger in 6-year-olds, as if the ability to distribute attention between the different locations (and not only to orient to the most probable location) developed between 6 and 8 years.
View Article and Find Full Text PDFThis study tests the hypothesis that the recognition of a face is facilitated when the face has previously been presented in a rapid rather than a slow view sequence. We used a sequential comparison task, in which a first face, rotating back and forth around a left or a right three-quarter view, was followed, after a 1-s delay, by a static view of a second face, with the same or a different viewpoint. We compared rapid (180 ms per view) and slow (720 ms per view) sequences to evaluate the timing constraints of temporal view association, and video and view sequences to evaluate the importance of motion smoothness.
View Article and Find Full Text PDFWe studied the role of the frontal lobes in orienting spatial attention and inhibiting attentional capture by goal-irrelevant stimuli, using a spatial cueing method in patients with frontotemporal dementia (FTD). Two blocks of trials were presented, one with non-predictive cues and the other with counter-predictive cues. FTD patients showed a global orienting deficit, with a greater difference between invalid and valid trials than age-matched controls.
View Article and Find Full Text PDFUnilateral spatial neglect (USN) was defined 30 years ago as "a failure to report, respond, or orient to stimuli that are presented contralateral to a brain lesion, provided that this failure is not due to elementary sensory or motor disorders" by Heilman and Valenstein (1979). Even though this definition still holds, the last 30 years have been characterized by a profusion of clinical descriptions, neuroanatomical investigations and theoretical models of neglect. This article summarizes the wealth of neuroanatomical, clinical and experimental data concerning USN, by focusing on attentional and spatial deficits.
View Article and Find Full Text PDFTo address the extent to which the visual foveal representation is split, we examine the case of a patient, M.B., suffering from a left mesial occipital lesion and presenting a pure left hemialexia and a right hemianopia with a spared area of the macula.
View Article and Find Full Text PDFTo explore the functioning of spatial attention in Huntington's Disease (HD), 14 HD patients and 14 age-matched controls performed a cued response time (RT) task with peripheral cues. In Experiment 1, cues were not informative about the future target location, thus eliciting a purely exogenous orienting of attention. At short stimulus-onset asynchrony (SOA), controls showed an initial facilitation for cued locations, later replaced by a cost (inhibition of return, IOR).
View Article and Find Full Text PDFWe report here on a single neuropsychological case study of a young girl, KH, who presented with Wilson's Disease (WD) associated with a peripheral spatial neglect dysgraphia without major problems in the standard clinical tests of spatial neglect. Few studies have demonstrated a visuospatial deficit in WD and to date there has been no report of neglect syndrome arising from WD. However, recent studies have demonstrated that neglect is frequently associated with brain damage including the primary site of WD, the basal ganglia.
View Article and Find Full Text PDFTwenty-six patients suffering from damage to the right side of the brain, 19 of whom exhibited signs of left neglect, as well as 32 matched controls, ran 3 spatial cuing tasks. Patients were also tested with 2 cancellation tests, a line-bisection test, the copy of a complex drawing, and a visual extinction procedure. Results first showed correlations between extinction and cancellation tests performance on one hand, and between line bisection and copy on the other hand.
View Article and Find Full Text PDFCan we build endogenous expectations about the locus of occurrence of a target without being able to describe them? Participants performed cue-target detection tasks with different proportions of valid and invalid trials, without being informed of these proportions, and demonstrated typical endogenous effects. About half were subsequently able to correctly describe the cue-target relationships ('verbalizers'). However, even non-verbalizer participants showed endogenous orienting with peripheral cues (Experiments 1 and 3), not depending solely on practice (Experiment 2).
View Article and Find Full Text PDFNeuropsychologia
January 2006
We compared the performance of a sustained attention task by children with epilepsy in either the frontal or temporal lobe. In a new simple task that specifically measures preparatory attention, developed recently by LaBerge, Auclair, and Siéroff [LaBerge, D., Auclair, L.
View Article and Find Full Text PDFDue to progress in the cognitive theories in the last twenty years, the description of attentional deficits associated with normal or pathological aging has substantially improved. In this article, attentional deficits are presented according to Posner theory, which describes three sub-systems in a global network of attention: vigilance, selective attention, command. This theory not only characterizes the functions of these subsystems, but gives precise indications about their anatomical and neurochemical substrates.
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