Process analysis of verbal fluency production following pallidal lesions and subthalamic nucleus stimulation

Abstracts 1 Archives of Clinical Nemopsychology 15 (2000) 653-850 715 measures. A series of 3 comprehensive neuropsychological evaluations separated by 2 years were completed, the first as a baseline, and the second and third assessments following different medication treatments. An analysis of longitudinal findings revealed a steady decline in cognitive ability over a 2-year period after baseline despite interferon beta treatment, prompting neurological and neuropsychological re-evaluation and subsequent medication change. Comprehensive neurometric assessment revealed significant improvement in cognitive functioning after glatiramer acetate treatment that was consistent with MRI and neurologic observations. These findings effectively illustrate the sensitivity of repeated neuropsychological evaluation in monitoring drug efftcacy and its utility as an important clinical tool in medical decision making. Process analysis of verbal fluency production following nucleus stimulation Trepanier LL, Saint-Cyr JA, Lang AE, Lozano AM. pallidal lesions and subthalamic There has been a renewed interest in neurosurgical interventions for Parkinson’s disease (PD), namely unilateral posteroventral pallidotomy (U-PVP) and chronic bilateral deep brain stimulation of the subthalamic nuclei (SIN-DBS). Recent cognitive outcome studies have indicated that measures of phonemic and/or semantic verbal fluency, already compromised in PD due to frontal-striatal dysfunction, appear to be the most consistently affected neurocognitive functions following these procedures. In order to understand the underlying cognitive processes involved in verbal fluency and hence, the possible nature of these post-operative verbal fluency deficits, a process analysis of pre- and posttest protocols was undertaken in 39 U-PVP patients and in 11 SIN-DBS patients over a l-year follow-up period. Fluency productions were re-analyzed for 2 components: clustering (i.e. the production of words within semantic or phonemic subcategories) and switching (i.e. the ability to shift between clusters). It is thought that clustering and semantic fluency are more related to temporallobe function while switching and phonemic fluency are more related to frontal-lobe function. As expected, post-operative declines were more consistently observed on switching for both surgical procedures, with no recovery of function over 1 year. Lateral&y effects were also noted following UPVP lesions. Left-sided lesions led to declines in switching on phonemic fluency but either side of lesion led to switching difficulties on semantic fluency. Verbal fluency has not recovered in any study published to date and this was found in the present study as well. It can be concluded that neurosurgical interventions for PD further disrupt the functional integrity of frontal-striatal circuitry. Attentional processing in Parkinson’s disease: hyperkentic and akenetic type Kraus CD, Iacono Rp: Burley r Freier K, Raggs M, Jenkins L. Parkinson’s disease (PD) is an idiopathic, progressive, neurologic disorder. This neurologic disorder affects approximately 1 in 100 people over age 60 in the United States (Bondi and Troster, 1997). This disease is a progressive degeneration of the monoaminergic dopaminergic systems (Wolters and Calne, 1989, Mirsky, et al., 1960). Neuropsychological studies regarding cognitive functioning in Parkinson’s disease (PD) have yielded inconsistent results. This inconclusiveness is probably related the fact that these studies have assumed that PD is a single disorder rather than a spectrum of disorders. Hyperkenetic (tremor dominant) and akinetic (axial symptoms) exhibit different symptoms, different neurochemistry and different underlying pathological mechanisms. Two subtypes of Parkinson’s disease were addressed, hyperkinetic and akinetic. In addition, normal aged matched adults were used  (...truncated)