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1.
Mov Disord ; 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31922295

RESUMO

OBJECTIVE: To determine the relationships between the motor phenotype and the presence of specific neuropsychiatric and neuropsychological disorders in patients with early motor-manifest Huntington's disease (HD). METHODS: From the Enroll-HD study, 3,505 individuals with HD who had ≤5 years of motor symptoms were classified based on the predefined parkinsonism/chorea index into chorea-dominant (n = 1125), parkinsonism-dominant (n = 867), and mixed-motor phenotype (n = 1513) groups. An analysis was performed on the results of the short Problem Behaviors Assessment. This test assesses patients for neuropsychiatric disorders such as depression, irritability/aggression, apathy, obsessive-compulsive behaviors, and psychosis as well as cognitive disorders by using neuropsychological tests such as the Stroop Interference test, Trail Making Test Part A and B, letter fluency, Symbol Digit Modality test, and animal fluency test. RESULTS: In these early motor-manifest HD individuals, motor phenotype was associated with neuropsychiatric and cognitive changes. Independent of the age of motor onset, motor duration and severity, CAG repeat expansion, and medication use, the parkinsonism-dominant group had more severe neuropsychiatric disorders (depression, apathy, obsessive-compulsive behaviors, and psychosis) and poorer performance on all cognitive tests than those patients in the mixed-motor phenotype and chorea-dominant groups. The patients in the chorea-dominant group had less apathy and depression than those in the mixed-motor phenotype group. CONCLUSIONS: In the early stage of motor-manifest HD, parkinsonism-dominant patients appear to have more severe neuropsychiatric disturbances and more cognitive impairments than those HD patients with chorea-dominant and mixed-motor phenotypes. Future studies should explore the brain mechanisms of these disorders and the possible treatments. © 2020 International Parkinson and Movement Disorder Society.

2.
Artigo em Inglês | MEDLINE | ID: mdl-31942921

RESUMO

BACKGROUND/OBJECTIVES: Whereas rare cases of hemispatial visual neglect have been reported in patients with a neurodegenerative disease, quadrantic visuospatial neglect has not been described. We report a patient with probable posterior cortical atrophy who demonstrated lower right-sided quadrantic visuospatial neglect, together with allocentric vertical neglect. METHODS/RESULTS: A 68-year-old man initially noted deficits in reading and writing. Subsequently, he developed other cognitive deficits. On vertical line bisections, he deviated upward, and on horizontal line bisections, he deviated to the left. These deviations together suggest that this man's neglect might be most severe in his right (head/body-centered) lower (below eye level) visual space. When attempting to perform vertical line bisections in all four egocentric quadrants, his upward deviations were largest in the right lower quadrant. On a cancelation test, he revealed bilateral lower (ventral) allocentric neglect but not egocentric neglect. This patient's magnetic resonance imaging revealed cortical atrophy, most prominent in the left parietal lobe. DISCUSSION: Previous research in stroke patients has demonstrated that the parietal lobes are important in mediating attention to contralateral and inferior visual space. The presence of left parietal atrophy may have induced this right lower (ventral) egocentric inattention as well as bilateral ventral allocentric inattention. Although to our knowledge there have been no prior reports of a patient with right lower quadrantic and lower vertical allocentric visuospatial neglect, patients are rarely tested for these forms of neglect, and this patient illustrates the importance of evaluating patients for these and other forms of neglect.

3.
J Clin Exp Neuropsychol ; : 1-10, 2020 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-31973657

RESUMO

Introduction: The Oblique Effect denotes superior performance for perceiving horizontal or vertical rather than diagonal or oblique stimuli. The current research investigated responding to oblique test stimuli in patients with mild cognitive impairment (MCI).Method: Four statistically-determined groups (n = 112) were studied; patients with little to no cognitive impairment (non-MCI, n = 39); subtle cognitive impairment (SCI, n = 15); amnestic MCI (aMCI, n = 28); and a combined mixed/dysexecutive MCI (mixed/dys MCI, n = 30). The ability to respond to oblique versus non-oblique test stimuli was assessed using the Judgment of Line Orientation Test (JOLO). Comprehensive neuropsychological assessment was also obtained. Between-group differences for JOLO oblique and non-oblique test stimuli were analyzed. Hierarchical linear regression models were constructed to identify relations between accuracy for oblique and non-oblique test items and neurocognitive domains.Results: The mixed/dys MCI group demonstrated lower accuracy for oblique test items compared to non-MCI patients. Accurate responding to oblique test items was associated with better performance on tests measuring executive control, processing speed, naming/lexical retrieval, and verbal concept formation. No between-group differences were seen for non-oblique items and these items were not associated with cognition.Conclusions:Significant impairment on oblique test items distinguished patients with multi-domain/dysexecutive MCI from non-MCI patients. Accurate responding to oblique test items was associated with a complex array of neuropsychological tests suggesting that multidimensional neuropsychological skills underlie the visuospatial reasoning abilities necessary for successful oblique line identification. Research associating responding to oblique versus non-oblique test stimuli using additional neuropsychological test paradigms, and MRI-defined neuroanatomical regions of interest may provide additional information about the brain-behavior relations that underlie MCI subtypes.

4.
J Alzheimers Dis ; 73(1): 63-71, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31815693

RESUMO

Alzheimer's disease (AD) and vascular dementia (VaD) are the two most common types of dementia. Although the combination of these disorders, called 'mixed' dementia, is recognized, the prevailing clinical and research perspective continues to consider AD and VaD as independent disorders. A review of recent neuropathological and neuropsychological literature reveals that these two disorders frequently co-occur and so-called 'pure' AD or VaD is comparatively rare. In addition, recent research shows that vascular dysfunction not only potentiates AD pathology, but that pathological changes in AD may subsequently induce vascular disorders. On the basis of these data, we propose that the neurobiological underpinnings underlying AD/VaD dementia and their neuropsychological phenotypes are best understood as existing along a clinical/pathological continuum or spectrum. We further propose that in conjunction with current diagnostic criteria, statistical modeling techniques using neuropsychological test performance should be leveraged to construct a system to classify AD/VaD spectrum dementia in order to test hypotheses regarding how mechanisms related to AD and VaD pathology interact and influence each other.

5.
J Neurol Sci ; 408: 116523, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31678902

RESUMO

OBJECTIVES: To identify the characteristics and prevalence of mild cognitive impairment in patients with motor-manifest Huntington's disease (HD) and to propose a new mild cognitive impairment (HD-MCI) classification for HD. METHODS: We included 307 motor-manifest HD participants from the ENROLL-HD study who completed the evaluation in four neurocognitive domains including executive functions, processing speed, language, and memory. Cognitive impairment in each domain was determined by age- and education-adjusted cutoffs (> 1.5 standard deviations below the mean). HD-MCI was defined as an impairment in at least one cognitive domain without a loss of functional independence (Function Independence Scale, FIS ≥85). Dementia (HD-Dem) was defined as at least two domains of cognitive impairment with functional impairment (FIS ≤80). RESULTS: At the onset of motor symptoms, MCI was present in 84% and dementia in 5% of patients. After 5 years of motor symptoms, 24% of participants met the criteria for MCI and 69% for dementia. Executive dysfunction was the most common impairment, being present in 70% of participants, followed by slowed processing speed in 67%. Language impairment was reported in 55% and memory deficits in 53%. MCI subtypes were classified as "Executive-predominant" (executive impairment and slowed processing speed), "Representational-predominant" (impaired language and memory) and "Mixed Executive-Representational". Executive-predominant MCI comprised 30%, Representational-predominant 15% and Mixed 55% of this cohort. CONCLUSION: MCI is highly prevalent in the early stage of motor-manifest HD. Three MCI subgroups are defined suggesting at the earlier stage of this disease the frontal-striatal-executive and/or the temporoparietal-representational functional network can be impaired.

6.
J Clin Exp Neuropsychol ; 42(1): 101-110, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31665971

RESUMO

Objective: Research on impairments of spatial attention has primarily investigated hemispatial neglect in brain-lesioned patients, revealing decrements in the allocation of attention to right versus left egocentric or allocentric hemispace. Whereas head trauma might injure those parts of the brain that allocate vertical attention, little is known about the influence of trauma on the allocation of visuospatial attention in vertical space. Thus, the goal of this study was to learn if chronic moderate-to-severe traumatic brain injury (m/sTBI) alters the allocation of vertical visuospatial attention as assessed by the Attention Network Task (ANT). The ANT assesses the influence of Posner-type spatial cues and distractors using an Eriksen flanker task.Methods: 12 chronic m/sTBI patients and 12 demographically-matched neurologically-healthy controls (HCs) completed a version of the ANT wherein trials were coded for cue and target locations above and below central visual fixation. Trial-wise reaction times (RT) and accuracy were subjected to mixed-model ANOVAs and planned contrasts.Results: These data were subject to secondary analyses, which revealed that across groups, median RTs were significantly faster when targets occurred above than below the central visual fixation (p < .01); however, only HCs' error rates differed as a function of target altitude. Unlike controls, m/sTBI survivors did not exhibit the anticipated upward error-rate attentional bias.Conclusions: As alteration of spatial attention can be a major cause of disability, present findings suggest that m/sTBI survivors exhibit this loss of normal upward attentional bias. Future studies are need to learn if these patients might benefit from treatment.

7.
Artigo em Inglês | MEDLINE | ID: mdl-31610738

RESUMO

Objectives: Leftward deviation on a horizontal line bisection test (pseudoneglect) might be induced by right hemispheric dominance for mediating spatial or global attention, or a hemispheric asymmetry in the ability to spatially disengage attention. With aging, this leftward bias is reduced, likely due to the aging-related deterioration of right hemisphere mediated functions (right hemi-aging) or hemispheric asymmetry reduction in old adults (HAROLD). Methods: Forty-seven healthy adults divided into younger and older groups performed a modified Posner spatial-attentional task. Results: Overall, younger individuals responded faster to left than right-sided imperative stimuli. In contrast, older participants did not reveal a right-left asymmetry to imperative stimuli. The younger group also revealed a strong inverse relationship between the reaction time to right valid cues and the leftward attentional bias while performing the line bisection task (pseudoneglect). Conclusions: Our results provide support for both the right hemisphere spatial-attentional dominance hypothesis of pseudoneglect and the right hemi-aging hypotheses.

8.
Neuropsychologia ; 135: 107236, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31654648

RESUMO

The oblique effect (OE) describes the visuospatial advantage for identifying stimuli oriented horizontally or vertically rather than diagonally; little is known about brain aging and the OE. We investigated this relationship using the Judgment of Line Orientation (JLO) in 107 older adults (∼age = 67.8 ± 6.6; 51% female) together with neuropsychological tests of executive functioning (EF), attention/information processing (AIP), and neuroimaging. Only JLO lines falling between 36-54° or 126-144° were considered oblique. To quantify the oblique effect, we calculated z-scores for oblique errors (zOblique = #oblique errors/#oblique lines), and similarly, horizontal + vertical line errors (zHV), and a composite measure of oblique relative to HV errors (zOE). Composite z-scores of EF and AIP reflected domains associated with JLO performance. Graph theory analysis integrated T1-derived volumetry and diffusion MRI-derived white matter tractography into connectivity matrices analyzed for select network properties. Participants produced more zOblique than zHV errors (p < 0.001). Age was not associated with zOE adjusting for sex, education, and MMSE. Similarly adjusted linear regression models revealed that lower EF was associated with a larger oblique effect (p < 0.001). Modular analyses of neural connectivity revealed a differential patterns of network affiliation that varied by high versus low group status determined via median split of zOblique and zHV errors, separately. Older adults exhibit the oblique effect and it is associated with specific cognitive processes and regional brain networks that may facilitate future investigations of visuospatial preference in aging.

9.
J Int Neuropsychol Soc ; 25(10): 1044-1050, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31543083

RESUMO

OBJECTIVES: Healthy young adults often demonstrate a leftward spatial bias called "pseudoneglect" which often diminishes with aging. One hypothesis for this phenomenon is an age-related deterioration in right hemisphere functions (right hemi-aging). If true, then a greater rightward bias should be evident on all spatial attention tasks regardless of content. Another hypothesis is a decrease in asymmetrical hemispheric activation with age (HAROLD). If true, older participants may show reduced bias in all spatial tasks, regardless of leftward or rightward biasing of specific spatial content. METHODS: Seventy right-handed healthy participants, 33 younger (21-40) and 37 older (60-78), were asked to bisect solid and character-letter lines as well as to perform left and right trisections of solid lines. RESULTS: Both groups deviated toward the left on solid line bisections and left trisections. Both groups deviated toward the right on right trisections and character line bisections. In all tasks, the older participants were more accurate than the younger participants. CONCLUSIONS: The finding that older participants were more accurate than younger participants across all bisection and trisection conditions suggests a decrease in the asymmetrical hemispheric activation of these specialized networks important in the allocation of contralateral spatial attention or spatial action intention.

10.
Cogn Behav Neurol ; 32(3): 208-213, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31517705

RESUMO

Corticobasal degeneration (CBD), a tau-related neurodegenerative disease, is characterized by limb rigidity, dystonia, myoclonus, apraxia, and cognitive deficits. We report a patient with probable corticobasal syndrome, a major phenotype of CBD, who revealed both lower vertical and proximal radial attentional neglect on line bisection tests. Brain imaging revealed bilateral parietal atrophy with hypometabolism in the bilateral parietal, dorsolateral prefrontal, and premotor cortices. Bilateral impairment in the dorsal attentional network reduces the allocation of spatial attention to lower and proximal space, causing lower vertical and proximal radial attentional neglect. Screening for various types of spatial neglect may be important in tailoring management and rehabilitation strategies for patients with CBD.

11.
J Clin Exp Neuropsychol ; 41(10): 1088-1096, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31441368

RESUMO

Background/Objectives: The allocation of attention can alter the perception of magnitude. When performing line bisections, young adults deviate leftward (pseudoneglect), a bias thought to be induced by right hemisphere dominance for allocating spatial attention. However, when performing body bisections young adults deviate rightward, suggesting left hemisphere dominance for allocating body-centered attention. With aging, there is a reduction of pseudoneglect thought to result from either an age-related decrease in right hemispheric functions (right hemi-aging) or from hemispheric asymmetry reduction in older adults (HAROLD). The goal of this study was to learn if there are tactile body-centered perceptual-attentional right-left asymmetries in that change with aging. Methods: The participants were younger and older healthy adults. Semmes-Weinstein Monofilaments were used to test for differences in the perceived magnitude of pressure differences between a reference stimulus and test stimuli applied to the right and left palmar thenar eminence. Results: Young adults perceived the magnitude of difference in the lightest pressure stimuli applied to the right hand as being greater than the older adults. Young adults perceived the magnitude of difference between the lightest pressure and reference applied to the right hand to be greater than the left hand, but older adults perceived a lighter stimulus greater on the left compared to the right. Conclusions: Whereas the right hemisphere appears to be dominant in mediating spatial attention, the left hemisphere may play a dominant role in the allocation of body-centered attention. Like the aging-related reduction of the visual perception of the magnitude (length) of the left side of a line, this tactile reduction in magnitude (pressure) perception in older adults suggests that with aging, there is a reduction of left-hemispheric mediated allocation of tactile attention, and this result is not fully consistent with either the HAROLD or hemi-aging models.

12.
Cogn Behav Neurol ; 32(1): 11-15, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30896572

RESUMO

BACKGROUND AND OBJECTIVE: Salience of emotional autobiographical memories may have temporal patterns associated with valence. Recall of negative emotional memories is often important in survival and well-being. Based on the possible survival value of negative memories, we posited that when given an open-ended request to recall either a sad or a happy memory, people are more likely to recall an older sad memory than a happy one. METHODS: We asked 20 healthy participants, aged 18-63 years, to freely recall happy and sad emotional memories and estimate the length of time that had passed since the recalled event had occurred. We analyzed the age of each memory based on valence. RESULTS: Sixteen of 20 participants volunteered a more remote sad than happy memory (P<0.05). Older participants' sad memories were more remote (P<0.05), but the ratio of happy to sad memories was not affected by age. CONCLUSIONS: Self-selected free retrieval of autobiographical happy and sad emotional memories reveals a time bias. Although the reason for this temporal dichotomy is unknown, it may be that engaging systems involved in defense and survival alters the encoding and/or retrieval characteristics of the memory that modify salience.


Assuntos
Envelhecimento/psicologia , Felicidade , Memória de Longo Prazo , Rememoração Mental , Tristeza , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
13.
J Int Neuropsychol Soc ; 25(1): 65-71, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30486914

RESUMO

OBJECTIVE: The objective of this study was to evaluate the impact of directed and sustained attention on the allocation of visuospatial attention. Healthy people often have left lateral and upward vertical spatial attentional biases. However, it is not known whether there will be an increase in bias toward the attended portion of the stimulus when volitional spatial attention is allocated to a portion of a stimulus, whether there are asymmetrical spatial alterations of these biases, and how sustained attention influences these biases. METHODS: We assessed spatial bias in 36 healthy, right-handed participants using a variant of horizontal and vertical line bisections. Participants were asked to focus on one or the other end of vertical or horizontal lines or entire vertical or horizontal lines, and then to bisect the line either immediately or after a 20 second delay. RESULTS: We found a significant main effect of attentional focus and an interaction between attentional focus and prolonged viewing with delayed bisection. Focusing on a certain portion of the line resulting in a significant deviation toward the attended portion and prolonged viewing of the line prior to bisection significantly enhanced the degree of deviation toward the attended portion. CONCLUSIONS: The enhanced bias with directed and sustained attention may be useful modifications of the line bisection test, particularly in clinical populations. Thus, future studies should determine whether prolonged viewing with delayed bisection and spatially focused attention reveals attentional biases in patients with hemispheric lesions who perform normally on the traditional line bisection test. (JINS, 2019, 25, 65-71).

14.
Artigo em Inglês | MEDLINE | ID: mdl-30322318

RESUMO

Creative production has been reported to decline with age. This study investigated age-related differences in creative verbal production. Participants were 30 younger and 30 older adults. Study testing included language and cognitive assessments and the experimental task wherein participants created short stories incorporating words that are not commonly related, semantically or associatively. The resulting stories were rated by independent blinded judges for originality, cohesion, appropriateness, and organization. Younger adults' stories were rated as being significantly more original and more appropriate. Integrating unrelated words to create original stories requires activating widely distributed lexical-semantic networks to develop novel associations. Potential decreased neural network connectivity due to white matter degradation, commonly seen in normal aging, as well as decrements in front-executive disengagement may have affected older adults' performance on this story creation task. Future research using neuroimaging may elucidate possible neuroanatomic correlates of age-related changes in associative creative production..

15.
Neurocase ; 24(4): 220-226, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30370810

RESUMO

With injury of the anterior two-thirds of the corpus callosum, each hemisphere's attentional bias to contralateral hemispace becomes manifest with each hand deviating ipsilaterally during line bisection tasks. Patients with infarctions in the right posterior cerebral artery distribution with occipital and splenial damage can also exhibit spatial neglect. The goal of this report is to learn the role of the splenium of the corpus callosum in mediating visuospatial attention. A right-handed woman with Marchiafava-Bignami disease and damage to the splenium of her corpus callosum without evidence of a mesial frontal, parietal, or occipital injury was assessed for spatial neglect with line bisections. When bisecting lines in her left hemispace with her right hand, she deviated to the right, but revealed no major deviations when the line was place in the midline, in right hemispace, or when bisecting lines with her left hand. This patient provides evidence that damage to the splenium can induce a special form of asymmetrical spatial neglect. This asymmetry might be related to the disconnected right hemisphere's ability to allocate attention to both right and left hemispaces with the disconnected left hemisphere's ability to allocate attention to the right but not left hemispace.


Assuntos
Corpo Caloso/patologia , Doença de Marchiafava-Bignami/complicações , Transtornos da Percepção/etiologia , Transtornos da Percepção/patologia , Adulto , Atenção , Corpo Caloso/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética , Feminino , Humanos , Testes Neuropsicológicos , Transtornos da Percepção/diagnóstico por imagem , Desempenho Psicomotor
16.
J Int Neuropsychol Soc ; 24(10): 1121-1124, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30165918

RESUMO

OBJECTIVES: Healthy individuals often have a leftward and upward attentional spatial bias; however, there is a reduction of this leftward bias with aging. The right hemisphere mediates leftward spatial attention and age-related reduction of right hemispheric activity may account for this reduced leftward bias. The right hemisphere also appears to be responsible for upward bias, and this upward bias might reduce with aging. Alternatively, whereas the dorsal visual stream allocates attention downward, the ventral stream allocates attention upward. Since with aging there is a greater atrophy of the dorsal than ventral stream, older participants may reveal a greater upward bias. The main purpose of this study was to learn if aging influences the vertical allocation of spatial attention. METHODS: Twenty-six young (17 males; mean age 44.62±2.57 years) and 25 healthy elderly (13 males; mean age 72.04±.98 years), right-handed adults performed line bisections using 24 vertical lines (24 cm long and 2 mm thick) aligned with their midsagittal plane. RESULTS: Older adults had a significantly greater upward bias than did younger adults. CONCLUSIONS: Normal upward attentional bias increases with aging, possibly due to an age-related reduction of the dorsal attentional stream that is responsible for the allocation of downward attention. (JINS, 2018, 24, 1121-1124).

17.
Neuropsychology ; 32(7): 843-849, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29985016

RESUMO

BACKGROUND/OBJECTIVES: Compound horizontal lines are composed of 2 segments of unequal length and width. Line bisection requires that the participants attend to the entire line (global attention). The longer segment often distracts participants, suggesting that attention directed to this segment (focal attention) disrupts the allocation of global attention. This study attempted to learn whether the allocation of focal attention to a line segment is distracted by global attention allocated to the entire line and whether there are right-left distraction asymmetries when allocating focal or global attention. METHOD: Twenty-four healthy adults (12 > 65 years old) attempted to bisect horizontal lines composed of 2 segments of unequal length, with the larger segment placed to the right or left. They were also asked to bisect the longer segment of these lines. RESULTS: When allocating focal attention to the larger segment, healthy participants were more distracted when the smaller segment was on the left than on the right. In contrast, when attempting to allocate global attention to the entire line, participants were more distracted when the larger segment was on the right side. There were no significant differences between older and younger participants. CONCLUSIONS: The asymmetrical global distraction during segment bisection might be related to the right hemisphere's dominance in mediating global attention and allocating attention leftward. In contrast, the asymmetrical focal distraction during full-line bisection might be related to the left hemisphere's dominance in mediating focal attention and allocating attention toward the right. (PsycINFO Database Record (c) 2018 APA, all rights reserved).


Assuntos
Atenção/fisiologia , Lateralidade Funcional/fisiologia , Percepção Espacial/fisiologia , Percepção Visual/fisiologia , Adolescente , Adulto , Idoso , Envelhecimento/psicologia , Dominância Cerebral/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estimulação Luminosa , Adulto Jovem
18.
J Clin Exp Neuropsychol ; 40(9): 887-894, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29614901

RESUMO

Background-objectives: When vertical lines are positioned above or below the center of the page, line bisection deviates toward the center of the page, suggesting that the edges of the page distract the allocation of attention to the line. A letter-character line (LCL) bisection requires both global and focal attention, to identify the target letter closest to the line's center. If more focal and less global attention is allocated to a LCL, more global attentional resources may be available and inadvertently allocated to the page. Alternatively, if the allocation of focal attention to a LCL inhibits global attentional processing, there may be less distraction by the page. METHOD: Twenty-four healthy adults (12 older) bisected vertical solid and character lines centered, or positioned closer to the top or bottom of the page. RESULTS: There was no difference between bisection of solid and character lines centered on the page. Page-related deviations were greater with character lines than solid line bisections, and greater for lines positioned toward the top than the bottom of the page. With lines positioned toward the top, the older participants' attempted bisections were higher than those of the younger participants. CONCLUSIONS: These results suggest that the allocation of focal attention increases global attentional distractibility and that global-background attentional distraction is greater when the vertical lines are placed in the upper part of the page. Older participants appeared to be less distracted when lines were placed toward the top of the page, but the reason for this age difference requires further research.


Assuntos
Atenção/fisiologia , Percepção Espacial/fisiologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Estimulação Luminosa , Adulto Jovem
19.
J Clin Exp Neuropsychol ; 40(9): 951-962, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29690819

RESUMO

OBJECTIVES: Several studies have reported that positive emotions are primarily mediated by the left hemisphere and negative emotions by the right hemisphere. Since each hemisphere primarily allocates attention toward the contralateral hemispace, we wanted to learn how inducing a spatial attentional orienting bias to right and left egocentric hemispace might influence the recognition and perception of visually presented emotional scenes. METHOD: Participants were 42 healthy, right-handed young adults. To induce a directional change in spatial attention, we used a horizontal prism adaptation (PA) method that trains participants to allocate attention in the opposite direction to the prism-induced deviation. After each PA, participants evaluated a set of affective (positive/neutral/negative) pictures from the Nencki Affective Picture System. Responses in each emotional category and reaction times were recorded and analyzed. RESULTS: There was no PA effects on reaction times between the experimental conditions. However, when compared to the control condition, both rightward and leftward PA resulted in a reduction of correctly recognized positive emotions as well as altering the perception of neutral and positive pictures as more emotionally negative. CONCLUSIONS: The results do not support the proposed left-right spatial attentional valence hypothesis. The reason why PA in both directions negatively altered emotion perception is not known. However, a portion of the dorsal visual stream, the parietal lobes, and especially the right parietal lobe, are critical for mediating horizontal egocentric spatial attention. The right hemisphere also mediates negative emotions, and the activation of this right hemispheric attention network may have induced the changes in perception found in this study. However, future studies are needed to further test this hypothesis.


Assuntos
Atenção/fisiologia , Emoções/fisiologia , Lateralidade Funcional/fisiologia , Percepção Espacial/fisiologia , Adulto , Feminino , Humanos , Masculino , Orientação/fisiologia , Tempo de Reação/fisiologia , Adulto Jovem
20.
Cogn Behav Neurol ; 31(1): 18-22, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29561315

RESUMO

Mixed transcortical aphasia (MTA) is characterized by decreased spontaneous speech, impaired naming, and poor comprehension, but with intact repetition. MTA has been reported to be the sequela of left hemisphere watershed infarction that isolates Wernicke's perisylvian arc. We report a 55-year-old right-handed woman who began having word-finding difficulty and then gradually developed impaired spontaneous speech, comprehension, and naming, but with intact repetition. Magnetic resonance imaging showed atrophy in the left frontal, parietal, and temporal lobes. This patient demonstrates that MTA can occur as a result of neurodegenerative disease. Further research is needed to learn whether progressive MTA is a late stage of primary progressive aphasia, examine the neuropathology associated with this syndrome, and identify treatment strategies.


Assuntos
Afasia/diagnóstico , Imagem por Ressonância Magnética/métodos , Afasia/patologia , Feminino , Humanos , Pessoa de Meia-Idade
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