Objective: Anterior temporal lobe resection (ATLR) is an effective treatment for drug-resistant temporal lobe epilepsy (TLE), although language deficits may occur after both left and right ATLR. Functional reorganization of the language network has been observed in the ipsilateral and contralateral hemispheres within 12 months after ATLR, but little is known of longer-term plasticity effects. Our aim was to examine the plasticity of language functions up to a decade after ATLR, in relation to cognitive profiles.
View Article and Find Full Text PDFKey Points: Cognitive impairment is common in CKD. Exercise targets multiple risk factors of cognitive decline. Meta-analysis found that exercise had a small but positive effect on cognitive function in CKD, albeit the quality of evidence was low.
View Article and Find Full Text PDFAim: A two-stage process, wherein self-report screening precedes the structured interview, is suggested for identifying individuals at clinical high-risk for psychosis (CHR-P) in community samples. Aim of this study was to screen a community youth sample from India for CHR-P using the two-stage method. Specific objectives were to assess concordant validity of the self-report measure and predictive validity of the two-stage method.
View Article and Find Full Text PDFWorking memory (WM) impairments are well recognized in schizophrenia patients (PSZ) and contribute to poor psycho-social outcomes in this population. Distinct neural networks underlay the ability to encode and recall visual and spatial information raising the possibility that profile of visual working memory performance may help pinpoint dysfunctional neural correlates in schizophrenia. This study assessed the resolution and associative aspects of visual working memory deficits in schizophrenia and whether these deficits arise during encoding or maintenance processes.
View Article and Find Full Text PDFThe emergence of COVID-19 was rapidly followed by infection and the deaths of millions of people across the globe. With much of the research and scientific advancement rightly focused on reducing the burden of severe and critical acute COVID-19 infection, the long-term effects endured by those who survived the acute infection has been previously overlooked. Now, an appreciation for the post-COVID-19 condition, including its neurological manifestations, is growing, although there remain many unknowns regarding the etiology and risk factors of the condition, as well as how to effectively diagnose and treat it.
View Article and Find Full Text PDFDisorders of the medial temporal lobe (MTL) adversely affect visual working memory (vWM) performance, including feature binding. It is unclear whether these impairments generalize across visual dimensions or are specifically spatial. To address this issue, we compared performance in two tasks of 13 epilepsy patients, who had undergone a temporal lobectomy, and 15 healthy controls.
View Article and Find Full Text PDFThe light-from-above prior enables observers to infer an object's three-dimensional shape-from-shading information. Young, Western adults implicitly assume the light source is placed not only above, but also to the left of, the observer. Previous evidence reached conflicting conclusions regarding the development of the assumed light source direction.
View Article and Find Full Text PDFIn oddball paradigms, infrequent stimuli elicit larger P300 event related potentials (ERPs) than frequent ones. One hypothesis is that P300 modulations reflect the degree of "surprise" associated with unexpected stimuli. That is the P300 represents how unlikely the stimulus is and this signal is then used to update the observer's expectations.
View Article and Find Full Text PDFLocal changes in cerebral blood flow are thought to match changes in neuronal activity, a phenomenon termed neurovascular coupling. Hypoxia increases global resting cerebral blood flow, but regional cerebral blood flow (rCBF) changes are non-uniform. Hypoxia decreases baseline rCBF to the default mode network (DMN), which could reflect either decreased neuronal activity or altered neurovascular coupling.
View Article and Find Full Text PDFBackground: Parkinson's disease (PD) is a chronic, neurodegenerative disorder affecting over 137,000 people in the UK and an estimated five million people worldwide. Treatment typically involves long-term dopaminergic therapy, which improves motor symptoms, but is associated with dose-limiting side effects. Developing effective complementary, non-pharmacological interventions is of considerable importance.
View Article and Find Full Text PDFObservers automatically orient to a sudden change in the environment. This is demonstrated experimentally using exogenous cues, which prioritize the analysis of subsequent targets appearing nearby. This effect has been attributed to the computation of saliency, obtained by combining features specific signals, which then feed back to drive attention to the salient location.
View Article and Find Full Text PDFParticipants are slower to report a feature, such as color, when the target appears on the side opposite the instructed response, than when the target appears on the same side. This finding suggests that target location, even when task-irrelevant, interferes with response selection. This effect is magnified in older adults.
View Article and Find Full Text PDFStudies investigating the functional organization of the medial temporal lobe (MTL) suggest that parahippocampal cortex (PHC) generates representations of spatial and contextual information used by the hippocampus in the formation of episodic memories. However, evidence from animal studies also implicates PHC in spatial binding of visual information held in short term, working memory. Here we examined a 46-year-old man (P.
View Article and Find Full Text PDFWhen judging the 3D shape of a shaded image, young observers assume that the light source is placed above and to the left. This leftward bias has been attributed to hemispheric lateralization or experiential factors. Since aging is associated with loss of hemispheric lateralization, in the current study we measured the effect of aging on the assumed light source direction.
View Article and Find Full Text PDFIntroduction: Historically, emotion regulation problems have been reported as a common consequence of right prefrontal cortex (rPFC) damage. It has been proposed that the rPFC, particularly the rIFG, has a key role inhibiting prepotent reflexive actions, thus contributing to emotion regulation and self-regulation. This study is the first to directly explore this hypothesis, by testing whether damage to the rIFG compromises the voluntary modulation of emotional responses, and whether performance on inhibition tasks is associated with emotion regulation.
View Article and Find Full Text PDFA commonly held view in both exogenous and endogenous orienting is that spatial attention is associated with enhanced processing of all stimuli at the attended location. However, we often search for a specific target at a particular location, so an observer should be able to jointly specify the target identity and expected location. Whether attention can bias dimension-specific processes at a particular location is not yet clear.
View Article and Find Full Text PDFLateralization of function is a fundamental feature of the human brain as exemplified by the left hemisphere dominance of language. Despite the prominence of lateralization in the lesion, split-brain and task-based fMRI literature, surprisingly little asymmetry has been revealed in the increasingly popular functional imaging studies of spontaneous fluctuations in the fMRI BOLD signal (so-called resting-state fMRI). Here, we show the global signal, an often discarded component of the BOLD signal in resting-state studies, reveals a leftward asymmetry that maps onto regions preferential for semantic processing in left frontal and temporal cortex and the right cerebellum and a rightward asymmetry that maps onto putative attention-related regions in right frontal, temporoparietal, and parietal cortex.
View Article and Find Full Text PDFActa Psychol (Amst)
November 2014
We examined the effect of a task-irrelevant dimension on response times in young adults and seniors. We used the Simon task with congruent trials where the target and manual response were on the same side, incongruent trials where the target and response were on opposite sides, and neutral trials where the target appeared along the vertical meridian. We observed two age-related effects.
View Article and Find Full Text PDFWhile sensory processes are tuned to particular features, such as an object's specific location, color or orientation, visual working memory (vWM) is assumed to store information using representations, which generalize over a feature dimension. Additionally, current vWM models presume that different features or objects are stored independently. On the other hand, configurational effects, when observed, are supposed to mainly reflect encoding strategies.
View Article and Find Full Text PDFWhat limits the ability to attend several locations simultaneously? There are two possibilities: Either attention cannot be divided without incurring a cost, or spatial memory is limited and observers forget which locations to monitor. We compared motion discrimination when attention was directed to one or multiple locations by briefly presented central cues. The cues were matched for the amount of spatial information they provided.
View Article and Find Full Text PDFWhen judging the 3D shape of a shaded image, observers generally assume that the light source is placed above and to the left. This leftward bias has been attributed to experiential factors shaped by the observers' handedness or hemispheric dominance. Others have found that experiential factors can rapidly modify the direction of the assumed light source, suggesting a role for learning in shaping perceptual expectations.
View Article and Find Full Text PDFExogenous attention is an involuntary, reflexive orienting response that results in enhanced processing at the attended location. The standard view is that this enhancement generalizes across visual properties of a stimulus. We test whether the size of an exogenous cue sets the attentional field and whether this leads to different effects on stimuli with different visual properties.
View Article and Find Full Text PDFThis study examines how brain damage can affect the cognitive processes that support the integration of sensory input and prior knowledge during shape perception. It is based on the first detailed study of acquired ventral simultanagnosia, which was found in a patient (M.T.
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