Sex and psychiatric comorbidity correlates of the premonitory urge for tic scale in youth with persistent tic disorders.

The premonitory urge for tics scale (PUTS) is a common self-report measure of premonitory sensations preceding tics. The present study aimed to examine the internal consistency and concurrent validity of the PUTS by sex and psychiatric comorbidity status; and explored interactions between sex and psychiatric comorbidity in predicting premonitory urge and tic symptom severity. Seventy-four youth and young adults with persistent tic disorders completed the PUTS, while their parents completed the parent tic questionnaire (PTQ) and a demographic measure. Independent samples t-tests revealed no significant sex differences in PUTS items or total score. The PUTS total score also did not significantly differ between participants with and without attention-deficit hyperactivity disorder (ADHD) and/or obsessive-compulsive disorder (OCD) comorbidity. Internal consistency did not significantly differ between females (α = 0.85) and males (α = 0.75), and those with comorbid ADHD and/or OCD (α = 0.83) relative to those without (α = 0.69). With respect to concurrent validity, the PUTS total was significantly correlated with PTQ tic frequency, intensity, number, and severity for males but not for females. Among those with ADHD and/or OCD, the PUTS total score was correlated significantly and strongly with tic number and moderately with tic intensity. Interactions between sex and psychiatric comorbidity performed using 2 × 2 analysis of variance did not significantly predict the PUTS total or PTQ subscale scores. Findings suggest sex and comorbidity status may influence premonitory urge expression. Results have implications for understanding and measurement of the premonitory urge.

Efficacy of tailored computer-based neurorehabilitation for improvement of movement initiation in Parkinson's disease.

While Parkinson's disease (PD) is considered a motor disorder, motor signs of PD can be exacerbated by cognitive dysfunction. We evaluated the efficacy of a computer-based cognitive rehabilitation training program designed to improve motor-related executive function. Thirty people with PD and 21 controls participated in the 10-day training. Training consisted of a two-phase button press task. First, subjects produced an externally cued (EC) digit sequence, typing numbers displayed on the computer screen. Second, subjects were prompted to generate the same sequence in the absence of the number display (internally represented sequence, IR). Sequence length was automatically adjusted to maintain 87% correct performance. Participants were evaluated before and after training using a fixed version of the training task, and generalization of training was assessed using measures involving IR motor sequencing, switching and activities of daily living. PD participants were divided into two groups, those who showed impairment in IR motor sequence production prior to training (N=14) and those whose performance was similar to controls (N=16). Following training the impaired PD group showed significantly greater reduction in sequence initiation and completion time and in error rate for IR conditions compared to the unimpaired PD and control groups. All groups improved on Trails B-A, and pre-training Trails B was identified as a predictor of training-based improvement in IR sequence completion time and error rate. Our findings highlight the importance of neurorehabilitation tailored to the specific cognitive deficits of the PD patient.

Neuropsychological and quality of life outcomes 12 months after unilateral thalamic stimulation for essential tremor.

OBJECTIVES: To evaluate the one year cognitive, mood state, and quality of life (QoL) outcomes of unilateral thalamic deep brain stimulation (DBS) for essential tremor (ET). METHODS: 40 patients diagnosed with ET completed comprehensive neuropsychological assessments about one month before and three and 12 months after DBS electrode implantation. Data were subjected to multivariate analyses, and significant results were further analysed using univariate techniques. RESULTS: Analyses revealed statistically significant improvements on a cognitive screening measure and in aspects of fine visuomotor and visuoperceptual functions, verbal memory, mood state, and QoL. No group-wise declines in cognition were observed, but more patients showed declines than improvements on language and visual memory tests. Semantic verbal fluency declined significantly in four (10%) of the patients. In these four patients, diminished lexical verbal fluency was present at baseline. CONCLUSION: Cognitive, mood, and QoL outcomes after one year of DBS for ET are favourable; there were no overall deleterious effects on cognition, and DBS was accompanied by a significant reduction in anxiety and improvements in quality of life. However, preoperative verbal fluency diminution may predispose to further fluency declines after DBS.

Neuropsychological deficits in essential tremor: an expression of cerebello-thalamo-cortical pathophysiology?

Few studies have been published regarding the neuropsychological characteristics of patients with essential tremor (ET), but preliminary findings suggest that mild attentional and executive dysfunction accompany the disorder. A consecutive series of 101 patients with ET referred for thalamotomy and/or thalamic deep brain stimulation candidacy work-up also underwent neuropsychological evaluation. Average neuropsychological test scores were calculated, along with the proportions of subjects whose scores fell within or more than one SD above or below the mean (using demographically corrected normative data). Significantly lower than average (T-score of 50) scores were evident on measures of complex auditory attention, visual attention and response inhibition, recall of a word list, verbal fluency, and visual confrontation naming. A significantly greater proportion of patients (ranging from about 34 to 60%) than might be expected on the basis of a normal distribution obtained scores more than one SD below the normative mean on select measures of attention, verbal fluency, immediate word list recall, semantic encoding, and facial matching. Consistent with prior research, notable, albeit clinically subtle, deficits in attention and select executive functions are evident in patients with ET. Although not specific to ET or cerebellar dysfunction, the observed pattern of cognitive deficits is consistent with cerebello-thalamo-cortical circuit dysfunction.

Depression in multiple sclerosis: relationship to planning ability.

Recent research has demonstrated deficits on effortful executive tasks involving planning in multiple sclerosis (MS) patients. Given the high prevalence of depression in MS and the commonly reported link between depression and performance on executive tasks, planning impairments in MS may be associated with depression. We compared the performance of depressed and nondepressed MS patients on a planning task (Tower of London-TOL) to evaluate this hypothesis. Compared with nondepressed MS patients, depressed MS patients made significantly (p < .05) more moves and took more time per trial on the TOL. A follow-up regression analysis was conducted that included the TOL and speeded attentional/working memory task indices found to be associated with depression in MS from the authors' prior reports. This analysis revealed that 25% of the variance in depression scores was predicted by the most sensitive speeded attentional/working memory task. Furthermore, this variance overlapped completely with variance predicted by the TOL-time/trial index. The only clearly nonspeeded task index, TOL-moves per trial, was associated with unique variance (8%) in predicting MS depression scores. These results suggest that slowed information processing speed and, secondarily, deficient nonspeeded central executive skill, may be core to the cognitive deficits characteristic of depressed MS patients.

Which symptoms of anxiety diminish after surgical interventions for Parkinson disease?

OBJECTIVE: The purpose of the current study was to address whether improvement in anxious symptoms after surgical treatment of Parkinson disease (PD) reflects a true reduction in anxiety as opposed to an epiphenomenon of parkinsonian symptom amelioration. BACKGROUND: Recent research suggests that anxiety is common in PD. An association between surgical intervention for PD and anxiety reduction has been reported; however, it is not clear which specific symptoms of anxiety improve. METHOD: Thirty-nine PD patients completed the Beck Anxiety Inventory (BAI) approximately 1 month before and 4 months after surgery. Twenty-four participants underwent unilateral pallidotomy, 10 underwent deep brain stimulating electrode implantation of the internal segment of the globus pallidus, 4 underwent thalamic deep brain stimulating electrode implantation, and 1 underwent left thalamotomy. RESULTS: Statistically significant reductions were found postoperatively in terms of BAI total score as well as neurophysiologic, autonomic, and subjective factors from the BAI. The panic factor did not significantly change after surgery, possibly secondary to limited power afforded by the sample size. CONCLUSIONS: Results suggest that surgical intervention for PD is associated with reduction in anxiety symptoms distinct from symptoms of PD. In other words, improvement in anxious symptoms reflects a true reduction in anxiety rather than simply being an epiphenomenon of parkinsonian symptom amelioration.

Metamemory and tested cognitive functioning in multiple sclerosis.

Metamemory, or one's knowledge and self-report of memory ability, has been researched extensively; however, few studies have examined it in multiple sclerosis (MS). Because impairment in cognitive domains besides memory may affect memory functioning, patients may self-report problems with memory that are indicative of impairment in cognitive domains besides memory. One goal of the current study was to test this hypothesis in MS. A group of 55 MS patients were administered a variety of cognitive tasks and a self-report metamemory measure; patients' significant others were also given a metamemory measure requiring them to rate patients' memory abilities. Results indicated that patients' metamemory reports were significantly (p < .05) correlated with verbal recall, attentional, and executive tasks. Significant other ratings of patients' metamemory were correlated with verbal recall and attentional measures. Stepwise regression analyses including all relevant cognitive and demographic variables indicated that only education and Symbol Digit accounted for significant independent variance in patients' current memory reports. Our results suggest: (1) subjective complaints of memory difficulties by MS patients reflect difficulty in cognitive domains besides memory, (2) MS patient self-reports of memory difficulty are at least as accurate as significant other reports, and (3) patients with more education are more accurate in their metamemory ratings. These findings have implications not only for a better understanding of metamemory in MS, but also for more effective treatment and rehabilitation of MS patients.

Neurovegetative symptoms in multiple sclerosis: relationship to depressed mood, fatigue, and physical disability.

Some authors have suggested that when evaluating depression in multiple sclerosis (MS) patients, neurovegetative symptoms should be discounted and/or not considered, given the ostensibly high overlap between symptoms of MS (e.g., sleep disturbance, fatigue) and neurovegetative symptoms of depression. A further assertion is that inclusion of items assessing neurovegetative symptoms may artificially inflate overall depression scores and that mood scales may provide more accurate indices of depression in MS patients. The current study investigated the possibility that some neurovegetative symptoms may be specifically related to MS patients' depressed mood and are not simply indicators of physical disability and/or fatigue. Seventy-six clinically definite MS patients in the northwestern United States were administered two depression inventories and measures of physical disability and fatigue as part of a larger study. Results revealed that one neurovegetative symptom--disinterest in sex--was uniquely associated with depressed mood, and other neurovegetative symptoms were associated with both depression and fatigue but not physical disability. The present findings suggest that certain neurovegetative symptoms are differentially associated with depression, fatigue, and physical disability in MS. Routinely discounting all neurovegetative symptoms when assessing depression in MS patients may thus be unwarranted.

The ecological validity of clinical tests of memory and attention in multiple sclerosis.

Ecological validity--the degree to which clinical tests of cognitive functioning predict functional impairment--has recently become an area of interest in neuropsychology. The current study used a sample of 31 cognitively and functionally impaired multiple sclerosis (MS) patients to determine if tests commonly used to assess memory and attentional functioning in MS are ecologically valid. Two methods of improving the ecological validity of cognitive testing were employed. Stepwise multiple regression analyses suggested that tests of memory and attention more analogous to everyday tasks are better predictors of functional impairment in MS than both standard clinical tests of memory and attention, and memory questionnaires completed by the patient or a significant other. Nonetheless, both standard clinical tests and more ecologically valid tests significantly predicted functional impairment. Importantly, they were not significantly correlated with one another, suggesting that the inclusion of both types of tests in evaluating MS patients is warranted.

Depression in multiple sclerosis: relationship to working memory capacity.

Recent research has shown that depression in multiple sclerosis (MS) is associated with deficits on cognitively demanding tasks. One explanation for this relationship is that depressed MS patients may have reduced working memory capacity. The present study was designed to test this hypothesis. Depressed MS patients were compared with nondepressed MS patients and nondepressed healthy controls on a task of working memory capacity (reading span) and a short-term memory task not taxing working memory capacity (word span). In support of the capacity-reduction model, compared with the nondepressed groups, depressed MS patients performed significantly worse on reading span (p<.001) but not on word span. Additionally, reading span was significantly correlated with capacity-demanding tasks shown to be impaired in depressed MS patients in previous reports. Results suggest that depressed MS patients are characterized by limited working memory capacity and that the central executive component of the working memory system may be most affected.

Depressed mood in multiple sclerosis: relationship to capacity-demanding memory and attentional functioning.

Because it is theorized that depression results in reduced available attentional capacity that, in turn, can explain the impaired performance on capacity-demanding tasks in depressed individuals, the authors predicted that multiple sclerosis (MS) patients with depressed mood would have difficulty with these types of tasks. Twenty depressed mood MS participants were compared with 41 nondepressed mood MS participants and 8 nondepressed mood controls on 5 attentional capacity-demanding clinical memory and attentional tasks and 3 tasks with minimal capacity demands. Depressed mood MS patients performed significantly worse than both nondepressed mood groups on the 3 speeded capacity-demanding attentional measures but not on any of the tasks requiring few capacity demands, supporting the authors' predictions. The possibility that the impaired performance of depressed mood MS patients on speeded attentional tasks was mediated by reduced verbal working memory capacity, impaired deployment of executive strategies that access working memory capacity, or psychomotor slowing is explored.