Tricia Zawacki

Emotional and personality changes following cingulotomy.

The effects of bilateral anterior cingulate cortex (ACC) lesions on emotional and personality functioning were studied. Patients undergoing cingulotomy for chronic intractable pain were assessed on the Minnesota Multiphasic Personality Inventory (MMPI), the Profile of Mood States (POMS), cognitive tests, and pain ratings, pre- and postsurgically. Patients with intractable pain, not treated with cingulotomy, served as controls. Cingulotomy patients experienced reductions in POMS-Tension, POMS-Anger, and MMPI Scale 7 (Psychasthenia) compared with baseline and the controls. POMS-Tension was significantly correlated with attention-intention performance. The results indicate that the ACC modulates emotional experience, related to self-perceived tension, and that there is relationship between the emotional and the attentional effects of cingulotomy.

Executive and emotional dysfunction in Machado-Joseph disease.

Machado‐Joseph disease (MJD) is an autosomal dominant spinocerebellar ataxia. Few studies have examined the neuropsychological and neurobehavioral profiles of patients with MJD. In this study, six individuals with MJD were given a battery of neuropsychological tests. Relative impairments on timed verbal attention tasks and verbal fluency (Stroop, Oral Symbol Digit Modalities, and Controlled Oral Word Association Test) were found. Other executive impairments also were seen on the Wisconsin Card Sorting Test, independent of motor dysfunction severity. Moderate‐ to severe levels of depressive symptoms were endorsed by four of the six patients, and caregivers observed increased apathy in the patients. Impaired executive and emotional functioning in MJD does not appear to be related to ataxia severity. These patients did not meet the criteria for dementia. General cognitive abilities, language, list learning, story recall, and untimed tasks of attention were within normal limits. Impaired executive abilities and emotional functioning in MJD patients is consistent with disruption of frontal‐subcortical systems.

The relationship of subcortical MRI hyperintensities and brain volume to cognitive function in vascular dementia.

The relationship between MRI findings (i.e., subcortical hyperintensities; SH, whole brain volume) and the cognitive dysfunction of vascular dementia (VaD) was examined. Participants included 24 persons that met NINDS-AIREN criteria for VaD (MMSE = 19.9 +/- 4.2) and underwent comprehensive neuropsychological assessment and MRI brain imaging. The volume of subcortical hyperintensities (SH) was strongly associated with executive-psychomotor performance, but not with performance across other cognitive domains or global cognitive functional level. Conversely, WBV was strongly associated with global cognitive functioning and performance across most cognitive domains (memory, language, visual integration), but not with executive-psychomotor functioning. The failure of SH to account for either the global dementia evident in these VaD patients or impairments across most cognitive domains suggests that deep subcortical white matter disease may only indirectly contribute to the global cognitive dysfunction of VaD. That WBV emerged as a stronger correlate of dementia raises further questions regarding the cerebral mechanisms that contribute to the development of VaD.

What have we learned about cognition in myasthenia gravis? : a review of methods and results

Most individuals with myasthenia gravis (MG) complain of cognitive impairment, but empirical studies of cognition in MG have produced mixed results. In the present review, we critically examined the methodology and results of previous studies that investigated cognition in MG. Results from our review revealed that none of the studies met at least 50% of criteria under review. The most common shortcomings of previous studies included small sample size, no exclusion for visual difficulties in patients, inadequate assessment of mood, and poor control for prednisone use. Despite these methodological difficulties, mild impairments on measures of learning have been identified. These findings need to be replicated with adequate control of potential confounds before any conclusions can be made regarding cognition in this disease. Suggestions for design of future studies are provided.

Performance on the Mattis Dementia Rating Scale in patients with vascular dementia: relationships to neuroimaging findings.

Impairment on screening measures such as the Mattis Dementia Rating Scale (MDRS) provides evidence of demen tia in patients with cerebrovascular disease. However, the relationships between neuroimaging findings and performance on the MDRS in vascular dementia (VD) have not been determined. In the present study, we exam ined the relationships between subcortical hyperintensity (SH) volume and whole brain volume (WBV) on the subscales and total score of the MDRS. Results revealed that SH accounted for a significant amount of variance on the Initiation/Perseveration and Construction subscales, whereas WBV accounted for a significant amount of vari ance on the Memory subscale. The total score on the MDRS was found to be significantly related to WBV but not SH. These results suggest that subcortical damage and brain volume account for different aspects of cognitive decline in VD and that overall cognitive impairment may reflect cortical and subcortical involvement. (J Geriatr Psychiatry Neurol 2001; 14:33-36).

MODELS OF SUBCORTICAL FUNCTIONS IN LANGUAGE: CURRENT STATUS

Abstract Recent models of subcortical functions in language are discussed. Some emphasis is placed upon whether the thalamus and basal ganglia function via neuroregulation or direct information processing, or perhaps they play no role at all in language. Regarding the basal ganglia, models vary from suggesting no functional significance for language, to hypothesizing a role in the release of cortically formulated segments into the speech output stream, to theorizing a pivotal part in the monitoring and selection of lexical alternatives. For the thalamus, suggested roles include participating with the basal ganglia in selection of lexical alternatives or release of formulated responses, semantic monitoring, or selective engagement of cortical areas necessary for different language processes. In general, theorists agree the thalamus plays some fundamental or supportive role in language, though no consensus has been reached about the nature of this role. It is less clear that the basal ganglia participate in primary or supportive functions for language. The importance of subcortical functions for understanding how brain systems produce language and cognition is noted.

Cerebellar toxicity of cytosine arabinoside: Clinical and neuropsychological signs

High -dose cytosine arabinoside (ARA-C) therapy administered for acute nonlymphocytic leukemia causes cerebellar toxicity.1 Complications are usually transient and mild but may be severe and permanent in rare cases. Autopsies have revealed that Purkinje cells are most vulnerable, but minor, patchy cell loss in molecular and granular layers of the cerebellum may also occur.1 Deep cerebellar nuclei are minimally affected. Aside from cerebellar signs such as ataxia, dysarthria, and oculomotor impairment, confusion and drowsiness have also been described.1 Neuropsychological performance has not been described in these patients. Our patient, who has an old and static lesion and known cerebellar pathology, may provide further insights into the controversial theories of the cerebellum’s role in cognition. A 38-year-old, left-hand–dominant woman was diagnosed with acute myelogenous leukemia in 1990. She was treated with chemotherapy, Adriamycin 76 mg and ARA-C 340 mg per day for 5 days via continuous infusion (CALGB protocol #9022). On day 34, she was given her first intensification of chemotherapy, which consisted of ARA-C 5.1 …

Single Photon Emission Computed Tomography, Magnetic Resonance Imaging Hyperintensity, and Cognitive Impairments in Patients With Vascular Dementia

Background. The relationship between subcortical hyperintensity (SH) on magnetic resonance imaging (MRI), cortical perfusion on single photon emission computed tomography (SPECT), and cognitive function is not well understood. The authors examined these relationships in individuals with vascular dementia (VaD), paying particular attention to frontal lobe function to determine whether the presence of SH on MRI was associated with frontal hypoperfusion on SPECT, which in turn would be associated with impairments of executive‐attention function. Methods. Patients with vascular dementia (n= 26) were assessed on neurocognitive tests and brain MRI and SPECT. SH volume was quantified from the axial T2‐weighted fluid attenuated inversion recovery MRI. Total counts of activation across voxels for 12 cortical regions of interest were determined from SPECT. Perfusion ratios of both total cortical and frontal activation relative to cerebellum activation were derived, and regression analyses were performed to determine the relationships between cognitive, MRI, and SPECT indices. Results. SH volume on MRI was significantly associated with frontal lobe perfusion, but not with global cortical perfusion as measured by SPECT. Frontal lobe perfusion did not consistently correlate with performance on measures of executive function, although both total and frontal perfusion ratios were significantly associated with other cognitive functions. Conclusions. These results suggest that a functional “disconnection” between the frontal lobes and subcortical structures does not fully account for the magnitude of global cognitive impairment in VaD. Cortical perfusion as measured by SPECT appears to be associated with cognitive performance, but not specifically executive‐attention dysfunction. Additional studies are needed to further examine the relationship between subcortical and cortical function in VaD.

The Global Deterioration Scale: Relationships to Neuropsychological Performance and Activities of Daily Living in Patients with Vascular Dementia

In the present study, we examined the relationships between ratings on the Global Deterioration Scale (GDS) and activities of daily living and cognitive function in 39 individuals with vascular dementia (VaD). The results of the study revealed significant correlations between GDS rating and performance on cognitive tests, including memory and overall cognitive ability. In addition, the GDS was significantly related to ratings of instrumental activities of daily living. Comparisons between patients with VaD with GDS scores between 4 and 6 (n = 21) and patients with scores between 2 and 3 (n = 18) revealed greater cognitive and functional deficits in the group with higher GDS scores. Further, the GDS score accurately classified 87% of the patients with VaD. These findings provide support for the validity of the GDS in general staging of dementia severity of VaD. (J Geriatr Psychiatry Neurol 2002; 15:50-54).

Sensitivity of the Dementia Rating Scale in Vascular Dementia: Comparison between Two Sets of Criteria to Define Cognitive Impairment

Background: The Dementia Rating Scale (DRS) is a common measure of cognitive function, but its sensitivity to identify deficits across cognitive domains in vascular dementia (VaD) remains unclear. Methods: We compared the sensitivity and specificity of two recommended cutoff scores of the DRS. Thirty-eight patients diagnosed with VaD participated in the current study. Results: The original recommendations resulted in poor sensitivity for the DRS total score and attention, construction, and memory subscales. The more recent recommendations greatly improved the sensitivity of the subscales and the total DRS score, but resulted in decreased specificity. Correlations between the specific DRS subscales and criterion measures of cognitive function revealed good convergent and divergent validity for most subscales. Conclusions: The DRS is a valid measure of cognitive dysfunction in VaD, but clinicians should consider using the more recent recommendations developed for AD to determine impaired performances in VaD.