Natasha Lowery

Neuropsychological impairment among manic, depressed, and mixed-episode inpatients with bipolar disorder.

Previous research has demonstrated broad neurobehavioral abnormalities in bipolar affective disorder (cf. G. Cassens, L. Wolfe, & M. Zola, 1990). However, there have been no comparisons of neuropsychological function across patients with manic, depressed, or mixed subtypes. In the present study, 37 manic, 24 mixed-episode, and 25 depressed bipolar I inpatients and 34 control subjects were administered a brief battery of neuropsychological tests. The multivariate and univariate effects of participant group on the neuropsychological measures were uniformly significant (p < .05). Planned contrasts revealed that the bipolar participants performed worse than the controls, and few differences existed between the 3 patient groups. Additionally, the bipolar groups were impaired on 50% of the test battery. These abnormalities were unlikely attributable to differences in psychiatric symptomatology, medical illness, comorbid psychiatric diagnoses, or medication status. Findings imply that acute mood disturbance during bipolar disorder yields significant neurobehavioral dysfunction.

Practice Effects on the WAIS-III Across 3- and 6-Month Intervals

Fifty-one participants (age M = 24.6; education M = 14.4 years) were administered the Wechsler Adult Intelligence Scale – Third Edition (WAIS-III) at baseline and at an interval of either 3 or 6 months later. Full Scale IQ (FSIQ), Verbal IQ (VIQ), Performance IQ (PIQ), Verbal Comprehension Index (VCI), Perceptual Organization Index (POI), and Processing Speed Index (PSI) scores improved significantly across time, whereas no significant change occurred on the Working Memory Index. Specifically, test scores increased approximately 3, 11, 6, 4, 8, and 7 points, respectively on the VIQ, PIQ, FSIQ, VCI, POI, and PSI for both groups. Notably, the degree of improvement was similar regardless of whether the inter-test interval was 3 or 6 months. These findings suggest that prior exposure to the WAIS-III yields considerable increases in test scores. Reliable change indices indicated that large confidence intervals might be expected. As such, users of the WAIS-III should interpret reevaluations across these intervals cautiously.

Comorbid anxiety corresponds with neuropsychological dysfunction in unipolar depression.

Introduction. Unipolar depressives seem apt to show neuropsychological impairment, particularly involving executive function and memory. Yet, not all depressed patients show such deficits. Major depressive illness shares a high rate of comorbid anxiety disorder, and anxiety disorders also tend to correspond with cognitive difficulties. Consequently, depressed individuals with comorbid anxiety disorders may be inclined to demonstrate greater neuropsychological dysfunction than those without anxiety disorders. Method. We compared nonpsychotic depressed inpatients with (n=22) and without comorbid anxiety disorders (n=30) to a group of control subjects (n=38) on a brief but broad battery of neuropsychological tests. Patients were tested during an inpatient admission, and data were collected retrospectively from available records. Results. Both groups of depressed patients showed worse memory function than the controls. Yet, executive dysfunction and psychomotor slowing were specific to the depressed group with comorbid anxiety. The comorbid anxiety group also had more impaired scores than either the nonanxious depressed group or the control group. The depressed group without a comorbid anxiety disorder demonstrated no significant slowing compared to the control group. Conclusions. Major depressive disorder corresponds with significant memory impairment, regardless of comorbid anxiety disorder. Yet, presence of a comorbid anxiety disorder coincides with deficits involving executive function and psychomotor slowing. Clinical and theoretical relevance of the data is discussed.

Self-generated learning in people with multiple sclerosis

Memory impairment is among the most common cognitive deficits in people with multiple sclerosis (MS). To remediate this problem, recent research has evaluated the benefits of self-generated encoding. These nascent investigations reveal that people with MS who have mild memory impairment demonstrate a significant memory benefit from self-generated encoding compared with didactic learning. To extend prior research, the present experiment included MS patients with moderate-severe, rather than just mild, memory impairment. Additionally, the experiment evaluated whether self-generated encoding improves memory for activities of daily living instead of abstract words. Specifically, the experiment determined whether self-generated encoding enhanced memory for names, appointments, and object locations. In agreement with and extending prior research, MS patients remembered more information if it was self-generated rather than didactically presented, and this finding occurred despite moderate-severe memory impairment. Furthermore, compared with didactic encoding, self-generation enhanced recall of activities of daily living. Implications of these findings for cognitive rehabilitation and the nature of memory impairment in MS are discussed.

Practice Effects on the Wisconsin Card Sorting Test–64 Card Version Across 12 Months

The Wisconsin Card Sorting Test (WCST: Heaton, Chelune, Talley, Kay, & Curtiss, 1993) is among the most commonly administered measures of executive function. Recently, a short form of the test was developed (WCST–64: Kongs, Thompson, Iverson, & Heaton, 2000), and it affords psychometric properties commensurate with the full version of the test. Yet, similar to other measures of executive function, relatively little is known concerning the effects of repeated administration on the WCST–64. Towards this end, 53 men (age M = 32.38) were administered the WCST–64 twice over 12 months, and scores on several indices improved significantly during this interval. Suggestions concerning the use of these measures in longitudinal research designs and clinical follow-up examinations are offered, and reliable change indices concerning these measures are included.

Self-reported executive dysfunction, neuropsychological impairment, and functional outcomes in multiple sclerosis

Although cognitive deficits are common in persons with multiple sclerosis (MS), the relationship between subjective complaints and objective impairment is sometimes obscured. To elaborate this issue, the present study examined the relationship between subjective complaints of dysexecutive syndrome, neuropsychological performance, and self-reported activities of daily living in 42 people with MS and 13 control participants. Regression analyses revealed that subjective complaints of impairment, measured by the Frontal Systems Behavior Scale (FrSBe), emerged as a significant predictor of neuropsychological deficit and poor adaptive function. Accordingly, subjective complaints of dysexecutive function in MS may serve as a potent indicator of cognitive and functional impairment. Implications for research and clinical practice are discussed.

Global-Local Visual Biases Correspond With Visual-Spatial Orientation

Within the past decade, numerous investigations have demonstrated reliable associations of global-local visual processing biases with right and left hemisphere function, respectively (cf. Van Kleeck, 1989). Yet the relevance of these biases to other cognitive functions is not well understood. Towards this end, the present research examined the relationship between global-local visual biases and perception of visual-spatial orientation. Twenty-six women and 23 men completed a global-local judgment task (Kimchi & Palmer, 1982) and the Judgment of Line Orientation Test (JLO; Benton, Sivan, Hamsher, Varney, & Spreen, 1994), a measure of visual-spatial orientation. As expected, men had better performance on JLO. Extending previous findings, global biases were related to better visual-spatial acuity on JLO. The findings suggest that global-local biases and visual-spatial orientation may share underlying cerebral mechanisms. Implications of these findings for other visually mediated cognitive outcomes are discussed.

FORUM Sex Differences on the WMS-III: Findings Concerning Verbal Paired Associates and Faces

Previous research suggests that women have better verbal learning than men, whereas there is little evidence of sex differences in nonverbal learning. The present study examined whether sex differences occur on subtests from the Wechsler Memory Scale-III (Wechsler, 1997). Verbal Paired Associates I & II (VPA) and Faces I & II were administered to 26 male and 26 female undergraduates. A measure of visual-spatial perception, the Judgment of Line Orientation Test, (JLO) was also administered. This was done to place the study within the context of an established literature concerning sex differences in cognition. To rule out potential confounds due to intelligence, WAIS-R FSIQs were estimated and used as covariates in statistical analyses. Women outperformed men on several VPA indices, with men scoring at the 25th percentile and women scoring at the 50th percentile. Although no differences were observed on Faces I & II, men outperformed women on JLO. Implications and recommendations concerning the clinical use of VPA are discussed.

Self-generated learning in people with multiple sclerosis: an extension of Chiaravalloti and DeLuca (2002).

Although memory impairment is common in people with multiple sclerosis (MS), few interventions have been tested to remediate forgetfulness in MS. Chiaravalloti and DeLuca (2002) examined the memory benefit of self-generated encoding over didactic presentation in people with MS and a control group. They found that self-generated encoding enhanced memory of MS patients and a control group alike. The present study extended this finding by examining self-generated encoding in memory-impaired MS patients as well. A control group and MS patients with and without memory impairment learned word-pairs that were either self-generated or didactically presented. All groups remembered more self-generated words than those that were read aloud, and severity of memory impairment failed to moderate this memory benefit. Implications of these findings for cognitive rehabilitation and the nature of memory impairment in MS are discussed.

Global–local visual processing in posttraumatic stress disorder

The purpose of this study was to examine a behavioral index of hemispheric asymmetry (i.e., visual hierarchical attention) in posttraumatic stress disorder (PTSD), a disorder characterized by anxiety and other emotional symptoms. A reaction time based, computerized, global-local visual paradigm was administered to 26 PTSD-diagnosed and 22 psychopathology-free right-handed, male Vietnam War zone veterans. Results indicated that PTSD-diagnosed veterans displayed slower reaction times to all targets than the no-mental disorders comparison sample. However, findings also revealed a Group x Target location interaction in which the PTSD group was slower than the no-disorders comparison sample to respond to local, but not global, targets. Moreover, relative global bias was greater among PTSD-diagnosed veterans than their no-diagnosis counterparts. Findings provide partial support for the hypothesis that PTSD may be associated with a functional cerebral asymmetry favoring the right hemisphere.