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Introduction: As the population ages, the prevalence of cognitive impairment is expanding. Given the recent pandemic, there is a need for remote testing modalities to assess cognitive deficits in individuals with neurological disorders. Self-administered, remote, tablet-based cognitive assessments would be clinically valuable if they can detect and classify cognitive deficits as effectively as traditional in-person neuropsychological testing., Methods: We tested whether the Miro application, a tablet-based neurocognitive platform, measured the same cognitive domains as traditional pencil-and-paper neuropsychological tests. Seventy-nine patients were recruited and then randomized to either undergo pencil-and-paper or tablet testing first. Twenty-nine age-matched healthy controls completed the tablet-based assessments. We identified Pearson correlations between Miro tablet-based modules and corresponding neuropsychological tests in patients and compared scores of patients with neurological disorders with those of healthy controls using t tests., Results: Statistically significant Pearson correlations between the neuropsychological tests and their tablet equivalents were found for all domains with moderate (r > 0.3) or strong (r > 0.7) correlations in 16 of 17 tests (p < 0.05). All tablet-based subtests differentiated healthy controls from neurologically impaired patients by t tests except for the spatial span forward and finger tapping modules. Participants reported enjoyment of the tablet-based testing, denied that it provoked anxiety, and noted no preference between modalities., Conclusions: This tablet-based application was found to be widely acceptable to participants. This study supports the validity of these tablet-based assessments in the differentiation of healthy controls from patients with neurocognitive deficits in a variety of cognitive domains and across multiple neurological disease etiologies., (© 2023 S. Karger AG, Basel.)

We evaluated the hypothesis that Brodmann's area (BA) 37 within left occipitotemporal cortex has at least two important functions in lexical processing. One role is the computation of case-, font-, location-, and orientation-independent grapheme descriptions for written word recognition and production (reading and spelling). This role may depend on the medial part of BA 37, in left midfusiform gyrus. The second role is in accessing modality-independent lexical representations for output, for naming and for reading and spelling of irregular or exception words. This role may depend on the lateral part of BA 37 in inferior temporal cortex. We tested these hypotheses in 234 participants with acute left hemisphere ischaemic stroke who underwent magnetic resonance imaging (MRI) and language testing within 48 hours of onset of stroke symptoms.

Stroke remains a primary cause of morbidity throughout the world mainly because of its effect on cognition. Individuals can recover from physical disability resulting from stroke, but might be unable to return to their previous occupations or independent life because of cognitive impairments. Cognitive dysfunction ranges from focal deficits, resulting directly from an area of infarction or from hypoperfusion in adjacent tissue, to more global cognitive dysfunction. Global dysfunction is likely to be related to other underlying subclinical cerebrovascular disease, such as white-matter disease or subclinical infarcts. Study of cognitive dysfunction after stroke is complicated by varying definitions and lack of measurement of cognition before stroke. Additionally, stroke can affect white-matter connectivity, so newer imaging techniques, such as diffusion-tensor imaging and magnetisation transfer imaging, that can be used to assess this subclinical injury are important tools in the assessment of cognitive dysfunction after stroke. As research is increasingly focused on the role of preventable risk factors in the development of dementia, the role of stroke in the development of cognitive impairment and dementia could be another target for prevention., (Copyright 2010 Elsevier Ltd. All rights reserved.)

Background: The National Institutes of Health Stroke Scale (NIHSS) has been criticized for limited representation of cognitive dysfunction and bias towards dominant hemisphere functions. Patients may therefore receive a low NIHSS score despite a fairly large stroke. A broader scale including simple cognitive tests would improve the clinical and research utility of the NIHSS., Methods: We studied 200 patients with acute non-dominant hemispheric stroke who underwent cognitive testing and had MRI with diffusion-weighted imaging (DWI) within 5 days of presentation. We measured DWI volumes and retrospectively calculated NIHSS scores. We used linear regression to determine the role of selected cognitive tests, when added to the NIHSS, in predicting DWI volume., Results: The NIHSS predicted DWI volume in a univariate analysis, as did total line cancellation and a visual perception task. In a multivariate model, using log-transformed variables, the NIHSS (p=0.0002), line cancellation errors (p=0.02) and visual perception (p=0.004) each improved prediction of total infarct volume., Conclusion: The addition of line cancellation and visual perception tasks significantly adds to the model of NIHSS alone in predicting DWI volume. We propose that these two cognitive tests, which together can be completed in 2-3 minutes, could be combined with the NIHSS to create an "NIHSS-plus" that more accurately represents a patient's ischemic tissue volume after a stroke. This scale requires further validation in a prospective study.

Previous investigations provide evidence for distinction between egocentric (viewer-centered) and allocentric (stimulus- or object-centered) hemispatial neglect. However, it has not been determined whether this dissociation is modality-independent or modality-specific. We identify the incidence of egocentric and allocentric neglect in visual and tactile modalities, as well as the frequency of their co-occurrences in each modality. One-hundred patients with acute, right supratentorial ischemic stroke were administered tests for egocentric and allocentric hemispatial neglect in visual (n=98) and tactile (n=58) modalities. The visual test consisted of a page of 30 circles; 10 with no gap, 10 with a gap on the right side, and 10 with a gap on the left. Patients were asked to circle all complete circles and cross out all circles with gaps. A tactile version consisted of the same stimulus types presented as raised circles. Patients were asked to explore the board of circles with their dominant hand and report whether each circle had a gap. To determine the presence of egocentric or allocentric neglect, each test was analyzed for a significantly higher number of errors on the contralesional versus ipsilesional side of the page/board, or of the stimulus, using the Chi square analysis. On the visual test, 17 patients exhibited egocentric neglect; four exhibited allocentric neglect; and only two exhibited both. In the tactile modality, 19 exhibited egocentric neglect; one exhibited allocentric neglect; and none demonstrated both. Only four patients showed egocentric neglect on both visual and tactile tests. We found one patient with bilateral lesions who showed left egocentric visual neglect and right allocentric tactile neglect. These data provide strong evidence that egocentric and allocentric neglect are distinct syndromes that often dissociate and likely reflect damage to different brain areas. They also show that selective egocentric or allocentric neglect can occur in visual or tactile modalities.

Relating cognitive deficits to the presence of lesions has been an important means of delineating structure-function associations in the human brain. We propose a voxel-based Bayesian method for lesion-deficit analysis, which identifies complex linear or nonlinear associations among brain-lesion locations, and neurological status. We validated this method using a simulated data set, and we applied this algorithm to data obtained from an acute-stroke study to identify associations among voxels with infarct or hypoperfusion, and impaired word reading. We found that a distributed region involving Brodmann areas (BA) 22, 37, 39, and 40 was implicated in word reading.

Objective: To determine the relationship between change in blood pressure during coronary artery bypass graft operations and early cognitive dysfunction., Design: Cohort study., Setting: Quaternary care facility. Patients Fifteen patients undergoing coronary artery bypass graft operations who were at high risk for postoperative stroke. Preoperative and intraoperative mean arterial pressures (MAPs) were measured in all patients. Intervention A subset of patients underwent preoperative and postoperative magnetic resonance imaging. Main Outcome Measure Change in cognitive performance, using the Mini-Mental State Examination and other simple cognitive tests., Results: A drop in MAP (preoperatively to intraoperatively) predicted a decrease in Mini-Mental State Examination score. When change in MAP was dichotomized (after excluding an outlier), subjects with a small decrease improved on the Mini-Mental State Examination by 1 point, whereas those with a large drop in MAP worsened by 1.4 points (P = .04)., Conclusion: A drop in MAP from a preoperative baseline may put patients at risk for early cognitive dysfunction after a coronary artery bypass graft operation.

We hypothesized that distinct cognitive processes underlying oral and written picture naming depend on intact function of different, but overlapping, regions of the left hemisphere cortex, such that the distribution of tissue dysfunction in various areas can predict the component of the naming process that is disrupted. To test this hypothesis, we evaluated 116 individuals within 24 h of acute ischaemic stroke using a battery of oral and written naming and other lexical tests, and with magnetic resonance diffusion and perfusion imaging to identify the areas of tissue dysfunction. Discriminant function analysis, using the degree of hypoperfusion in various Brodmann's areas--BA 22 (including Wernicke's area), BA 44 (part of Broca's area), BA 45 (part of Broca's area), BA 21 (inferior temporal cortex), BA 37 (posterior, inferior temporal/fusiform gyrus), BA 38 (anterior temporal cortex) and BA 39 (angular gyrus)--as discriminant variables, classified patients on the basis of the primary component of the naming process that was impaired (defined as visual, semantics, modality-independent lexical access, phonological word form, orthographic word form and motor speech by the pattern of performance and types of errors across lexical tasks). Additionally, linear regression analysis demonstrated that the areas contributing the most information to the identification of patients with particular levels of impairment in the naming process were largely consistent with evidence for the roles of these regions from functional imaging. This study provides evidence that the level of impairment in the naming process reflects the distribution of tissue dysfunction in particular regions of the left anterior, inferior and posterior middle/superior temporal cortex, posterior inferior frontal and inferior parietal cortex. While occipital cortex is also critical for picture naming, it is likely that bilateral occipital damage is necessary to disrupt visual recognition. These findings provide new evidence that a network of brain regions supports naming, but separate components of this network are differentially required for distinct cognitive processes or representations underlying the complex task of naming pictures.

We hypothesized that a modified version of the Frontal Behavioral Inventory (FBI-mod), along with a few cognitive tests, would be clinically useful in distinguishing between clinically defined Alzheimer's disease (AD) and subtypes of frontotemporal lobar degeneration (FTLD): frontotemporal dementia (dysexecutive type), progressive nonfluent aphasia, and semantic dementia. We studied 80 patients who were diagnosed with AD (n = 30) or FTLD (n = 50), on the basis of a comprehensive neuropsychological battery, imaging, neurological examination, and history. We found significant between-group differences on the FBI-mod, two subtests of the Rey Auditory Verbal Learning Test (verbal learning and delayed recall), and the Trail Making Test Part B (one measure of 'executive functioning'). AD was characterized by relatively severe impairment in verbal learning, delayed recall, and executive functioning, with relatively normal scores on the FBI-mod. Frontotemporal dementia was characterized by relatively severe impairment on the FBI-mod and executive functioning in the absence of severe impairment in verbal learning and recall. Progressive nonfluent aphasia was characterized by severe impairment in executive functioning with relatively normal scores on verbal learning and recall and FBI-mod. Finally, semantic dementia was characterized by relatively severe deficits in delayed recall, but relatively normal performance on new learning, executive functioning, and on FBI-mod. Discriminant function analysis confirmed that the FBI-mod, in conjunction with the Rey Auditory Verbal Learning Test, and the Trail Making Test Part B categorized the majority of patients as subtypes of FTLD or AD in the same way as a full neuropsychological battery, neurological examination, complete history, and imaging. These tests may be useful for efficient clinical diagnosis, although progressive nonfluent aphasia and semantic dementia are likely to be best distinguished by language tests not included in standard neuropsychological test batteries.

The spatial neglect syndrome, defined by asymmetric attention and action not attributed to primary motor or sensory dysfunction and accompanied by functional disability, is a major cause of post-stroke morbidity. In this review, we consider the challenges and obstacles facing scientific researches wishing to evaluate the mechanisms and effectiveness of rehabilitation interventions. Spatial neglect is a heterogeneous disorder, for which consensus research definitions are not currently available, and it is unclear which of the deficits associated with the syndrome causes subsequent disability. We review current opinion about methods of assessment, suggest a rational approach to selecting therapies which requires further study, and make systems-level and theoretical recommendations for building theory. We lastly review some creative questions for consideration in future research.

Objective: Evaluate long-term changes in cognition after ventriculoperitoneal shunt insertion in patients with idiopathic normal pressure hydrocephalus., Background: Although studies have indicated that treatment of normal pressure hydrocephalus with ventriculoperitoneal shunt improves gait, effects of treatment on cognition have been inconsistent. Several studies have reported no significant improvement on neuropsychological tests in patients with idiopathic normal pressure hydrocephalus. Selection of candidates for shunt surgery using a trial of controlled spinal fluid drainage via lumbar catheter may result in more consistent improvement in cognition., Design/methods: This was a prospective, longitudinal study of performance on neuropsychological tests before and 6 to 12 months after insertion of a ventriculoperitoneal shunt in 10 patients with idiopathic normal pressure hydrocephalus who showed improvement in at least 1 clinical symptom with temporary lumbar drainage. Nonparametric tests were used to evaluate change., Results: Significant group improvements at follow-up were demonstrated on tests of verbal memory as well as in 1 test of psychomotor speed. Eight of 10 patients showed improvement by more than 1 standard deviation on at least 1 memory test. Six of 10 patients improved significantly on more than 50% of the tests administered., Conclusions: Patients with idiopathic normal pressure hydrocephalus who show clinical improvement (in any symptom) after lumbar drainage are likely to show significant long-term improvement in memory after ventriculoperitoneal shunt.

We carried out baseline and short-term follow-up MRI, including perfusion-weighted imaging (PWI) and tests of neurologic and cognitive function on 15 consecutive patients with large-vessel ischemic stroke who showed a persistent large perfusion-diffusion mismatch at enrollment up to seven days after the onset of symptoms. Of these, ten underwent induced blood pressure elevation with phenylephrine and oral medications (in eight) or intravenous fluids (in two) with the goal of improving perfusion; five had no such treatment. Significant functional improvement was defined by a reduction of 3 or more points on the NIH stroke scale (NIHSS). Significant improvement in perfusion was defined by a reduction in the volume of hypoperfused brain by 30 cc on PWI using time-to-peak (TTP) maps, without enlargement of the infarct. There was a strong, statistically significant association between improved function and improved perfusion: six (75%) of eight patients who improved in function, but none of the seven who did not, showed a reduction in volume of hypoperfused brain. All six patients who met the perfusion goal, and only two (22%) of nine who did not showed significant functional improvement (Fisher's exact: P < 0.01). There were no differences between patients who improved functionally and those who did not with respect to age, initial volume of abnormality on DWI or PWI, initial NIHSS, or changes on DWI. These findings indicate that reduction in volume of hypoperfused brain on PWI is a marker of response to treatment to improve perfusion even in subacute stroke and that partial reperfusion of regions of salvageable but dysfunctional tissue is a mechanism of improved function associated with induced blood pressure elevation.

Background and Purpose: Many studies have reported frequent cognitive deficits associated with subarachnoid hemorrhage (SAH) and aneurysm repair. One study found more severe cognitive deficits after clipping than coiling of aneurysms, raising the possibility that deficits are due to surgery instead of SAH itself. This possibility was directly addressed by evaluating the cognitive effects of surgery without SAH. The goal of this study was to identify changes in cognitive function associated with surgical clipping of unruptured intracerebral aneurysms., Methods: A consecutive series of 25 patients who underwent surgical clipping of >or=1 unruptured intracerebral aneurysm were tested within 1 week preoperatively and again postoperatively (before hospital discharge and at 3-month follow-up if they had deficits at discharge) on a neuropsychological battery. Different forms of each test were used preoperatively and postoperatively to reduce practice effects. Paired t tests were used to examine differences between preoperative and postoperative test scores across individuals., Results: On most tests, there was no significant change between preoperative and postoperative scores. A significant decline in accuracy before hospital discharge was found only in figure copying (P<0.04) and associative learning (P<0.01), and significant slowing was found on 1 test (P<0.01). Even on these tests, only 3 of 25 patients showed significant deterioration. All but 1 patient returned to baseline by the 3-month follow-up., Conclusions: We found no evidence of subtle cognitive deficits resulting from aneurysm clipping alone, suggesting that the common impairments after surgery for ruptured aneurysms are due to SAH itself, complications of SAH such as vasospasm or hydrocephalus, or perioperative stroke.

Objectives: To determine the frequency and severity of neuropsychological impairments associated with aneurysmal subarachnoid haemorrhage, and associated with repair of intracerebral aneurysms., Methods: Two groups of patients who underwent repair of intracerebral aneurysms were studied: patients with unruptured aneurysms (n=20) and patients with ruptured aneurysms (n=27). All patients were administered a battery of standardised neuropsychological tests about 3 months after surgery. A subset of 12 patients with unruptured aneurysms were administered the battery both before and after elective repair of the aneurysm(s). A subset of six patients with ruptured aneurysms were given the test at both 3 months and 1 year after surgery., Results: As previously reported for patients with ruptured aneurysms, patients with both ruptured and unruptured aneurysms performed, as a group, significantly below published norms on many of the neuropsychological tests after surgery. However, there were significant differences between preoperative and postoperative performance in the unruptured aneurysm group only on a few tests: measures of word fluency, verbal recall, and frontal lobe function. Performance of patients with ruptured aneurysms was significantly below that of patients with unruptured aneurysms only on a few tests of verbal and visual memory. In addition, group differences compared with published norms reflected severely impaired performance by a minority of patients, rather than moderately impaired performance in a majority of patients., Conclusions: Although patients who undergo repair of ruptured aneurysms perform, as a group, below published norms on many neuropsychological tests, significant impairments are seen in a minority of patients. Some of the impairments are associated with subarachnoid haemorrhage, whereas others (found in patients who underwent repair of unruptured aneurysms) are due to general effects of neurosurgery and perioperative management. Finally, some of the postoperative deficits are merely a reflection of premorbid weaknesses.