Robert D. Rhodes

Anxiety and depression severity are related to right but not left onset Parkinson's disease duration

Depression and anxiety have both been associated with relative left frontal hypoactivation and the motor symptoms of Parkinsons disease typically begin in a lateral or asymmetrical fashion. Hence, PD patients with right hemibody onset may experience heightened depression and anxiety. However, research is mixed regarding whether right or left hemibody onset PD is associated with elevated levels of depression and anxiety. This literature, though, has not considered the potential moderating variable of disease duration. We hypothesized that disease duration would be positively correlated with measures of depression and anxiety in right but not left hemibody onset PD patients. The results indicated that scores on the Geriatric Depression Scale, Beck Depression Inventory-II, and the State Trait Anxiety Scale - State correlated positively with disease duration, but only in the right hemibody onset group of PD patients. Thus, right hemibody onset PD is associated with more severe depressive and anxiety symptoms, but only when disease duration is considered.

HOSTILITY AS A MODERATOR OF PHYSICAL REACTIVITY AND RECOVERY TO STRESS

This experiment was designed to assess differences in physiological reactivity and recovery to stress among low- and high-hostile men. Specifically, 25 low- and 25 high-hostile undergraduates were identified using the Cook-Medley Hostility Scale (Cook & Medley, 1954). To ensure homogeneity, all subjects were right-handed and had a general right hemibody preference, as indicated by a score of +7 or higher on the Coren, Porac, and Duncan Laterality Test (Corer, Porac, & Duncan, 1979). All subjects underwent a traditional cold-pressor stressor test. Physiological measures heart rate, systolic blood pressure, and diastolic blood pressure were recorded before the stressor (Prestress), after the stressor (Poststress), and then again 9 min later (Recovery). Increased physiological arousal between pre- and poststress measurements was used as an indicator of reactivity. Subsequent decreases in physiological arousal were used as recover measures. Given the current models of negative emotion and hostility, it was expected that high-hostiles, relative to low-hostiles, would evidence increased physio logical arousal and decreased recovery to stress. Interestingly, high-hostiles experienced significantly greater reactivity to stress in heart rate only, and no group differences were found with regard to recovery. Results are discussed in terms of previous research and current models of emotion.

Quantitative electroencephalographic analyses of cardiovascular regulation in low- and high-hostile men

This experiment was primarily designed to identify higher cortical correlates of cardiovascular arousal. Low- and high-hostile right-handed undergraduate men were identified using the Cook-Medley Hostility Scale (CMHS; Cooke & Medley, 1954). All participants (N = 30) completed the cold-pressor paradigm. Cardiovascular (heart rate, systolic blood pressure, and diastolic blood pressure) and electroencephalographic (beta magnitude) data were collected before and after the stressor. As predicted, high-hostiles showed greater increases of heart rate and systolic blood pressure to the Stressor relative to low-hostiles. The primary findings of this research include significantly greater beta magnitude recorded by the T3, relative to the F7, electrode among low-hostiles. This may suggest that low-hostiles experience left-frontal disinhibition of left-temporal regions, thereby strengthening cardiovascular regulation during the cold-pressor stress. In addition, irrespective of condition, high-hostiles evidenced significantly greater beta magnitude at regions corresponding to the F7 and F8 electrodes. This perhaps suggests that high-hostiles have a relative inability to increase their rostral modulation of posterior systems related to cardiovascular reactivity/regulation.

Quantitative EEG diagnostic confirmation of expressive aprosodia

Quantitative electroencephalography (QEEG) was used to confirm predictions emanating from the neuropsychological examination of an adolescent with expressive aprosodia. Previous research has indicated that expressive deficits in prosody can be caused by cerebral damage to the right hemisphere region homologous to Brocas area. The neuropsychological evaluation of this individual indicates probable right anterior cerebral dysfunction. Taken together, a priori hypotheses included a relative deficit in cerebral arousal of right-relative to left-frontotemporal regions. EEG results confirm the hypothesis and provide case study evidence for both: (a) right anterior mediation of prosodic expression as well as (b) support for the inclusion of QEEG as part of a clinical neuropsychological evaluation.

Verbal and visuospatial memory in lateral onset Parkinson disease: time is of the essence.

ObjectiveThis investigation sought to study immediate and delayed verbal and visuospatial recall in Parkinson disease (PD) patients with left hemibody (LHO) and right hemibody (RHO) onset of motor symptoms and to examine the role of mental processing speed in recall of this information. BackgroundResearch is mixed regarding material specific memory impairments in LHO and RHO PD. However, earlier research has not used a factorial approach in investigating material specific memory in LHO and RHO PD. We hypothesized that LHO PD patients would exhibit an increase in performance following the delayed verbal free recall trial and either decline or stability in performance on the delayed visuospatial free recall trial. The opposite pattern was hypothesized for RHO PD patients. MethodThe Hopkins Verbal Learning Test-revised (HVLT-R) and the Brief Visuospatial Memory Test-revised (BVMT-R) were administered to a sample of 28 LHO PD patients and 36 RHO PD patients. The Stroop Color-word Test was administered as a measure of mental processing speed. ResultsThe results indicated that the RHO group experienced a significant decline in performance on verbal free recall from the immediate to the delayed trials and a significant improvement in performance from the immediate to the delayed visuospatial free recall trials. Additionally, a significant negative correlation was found between mental processing speed and changes in recall from the immediate to the delayed conditions for the RHO group. ConclusionsThese results indicate that the RHO PD group experienced a significant decline in verbal free recall and a significant improvement in visuospatial free recall from the immediate to the delayed trials and that the LHO PD patients experienced no significant changes. Further, mental processing speed appears to influence the recall of information from the immediate to the delayed conditions.

Anxiety Affects Working Memory Only in Left Hemibody Onset Parkinson Disease Patients

ObjectiveThis investigation sought to examine the potential moderating influence of heightened anxiety on working memory in Parkinson disease (PD) patients. Further, we wanted to determine whether this moderating influence of anxiety differentially affects PD patients with left hemibody (LBH) versus right hemibody (RHB) onset of motor symptoms. BackgroundResearch has examined the neurocognitive effects of depression in PD. However, a paucity of research has examined the effects of heightened anxiety in PD. We predicted that LHB PD patients with heightened anxiety would perform worse on a measure of working memory than RHB PD patients. MethodA total of 59 PD patients completed the state-trait anxiety inventory and were also administered the digit span subtest of the Wechsler Memory Scale—III. ResultsThe results supported the hypotheses, indicating that the LHB PD patients with heightened anxiety performed significantly worse than the RHB PD patients with heightened anxiety and the LHB PD patients with low anxiety. ConclusionsThese findings suggest that left hemibody onset PD patients may experience more disability in their activities of daily living. Future research should explore whether differences also exist between PD patients with and without the diagnosed anxiety disorders.

Reduced Verbal Learning Associated With Posterior Temporal Lobe Slow Wave Activity

Functional imaging has revealed that during verbal-word learning there is activation of the left posterior temporo-parietal region (PTPL). The purpose of this study was to learn if differences in the ability of normal people to learn might be accounted for by differences in electrophysiological (EEG) measures of activation of their left, but not right, PTPL. The Rey Auditory Verbal Learning Test (RAVLT) was administered to 42 men without neurological diseases. Delta magnitude, as measured by quantitative electroencephalography (QEEG), was recorded from the left and right PTPL while the participants sat quietly with their eyes closed. The magnitude of delta EEG activity is inversely proportional to cerebral activation. Based on delta magnitude, comparison groups were created by separating those with low and high delta at the left and right PTPL. Cumulative word learning (CWL) on the RAVLT was computed by subtracting the number of words recalled on the first learning trial from the highest number of words recalled on the fourth or fifth trial and multiplying this difference by the total words recalled during all 5 learning trials. The group with a greater magnitude of left PTPL delta activity had a significantly poorer CWL scores than those with less delta, but the CWL scores of the group with a greater magnitude of delta of the right PTPL was no different that the group with less right-sided delta. No significant differences emerged at any frontal or parietal electrode site. Decreased activation of the left, but not right, PTPL appears to be associated with a decreased verbal leaning ability. This article not subject to United States copyright law.

Verbal learning in Alzheimer's disease: cumulative word knowledge gains across learning trials.

Research regarding learning in Alzheimers disease (AD) patients has been mixed. Learning capacity might be better indexed using a score that reflects the interaction between the learning slope and total recall, referred to as the Cumulative Word Learning (CWL) score. We compared a group of AD patients to normal participants using a traditional index of learning and the CWL score that were derived from the Hopkins Verbal Learning Test-Revised (HVLT-R). The HVLT-R is a supra-span, list-learning test containing 12 words from three semantic categories. The results indicated that the sample of AD patients performed within the average range, using the traditional learning z score. Although mild AD patients were not found to differ from controls in the traditional learning z score, a significant difference was noted for the CWL score. The moderate AD patients differed from the normal controls in both learning measures. Furthermore, unlike the traditional learning score, the CWL score was a significant predictor of overall cognitive functioning, as indexed using their Mini-Mental State Examination (MMSE) score. Thus, the CWL score might be a more sensitive indicator overall of total learning capacity and may be useful in staging Alzheimers disease because of increased resilience to floor effects.

Cessation of long-term naltrexone administration: longitudinal follow-ups

Longitudinal follow-ups of the cessation of long-term Naltrexone administration (1 year of drug therapy) were conducted with a young woman (in her early 30s) with profound mental retardation who had previously displayed dramatic decreases in her self-injurious behaviors (SIB) both during, and for a period of at least 6 months following termination of drug treatment. After 2 and 4 years, post-Naltrexone therapy, the subject continued to exhibit near-zero rates of SIB episodes despite significant turnovers in her direct care staff by the 2-year follow-up, and changes in her physical/living environment and fellow residents by 4-year follow-up. These findings provide further support to the idea that long-term Naltrexone administration may result in highly durable reductions in SIB long after treatment ends and argue against certain aspects of the subjects environment affecting her rates of SIB significantly. These results are discussed in light of the endogenous opiate system theories of SIB. A functional analysis and discussion of the effectiveness of behavioral treatments for her few remaining SIB episodes are also provided.

Quantitative Electroencephalography (QEEG) and Neuropsychological Syndrome Analysis

The ideographic, syndrome analysis and the nomothetic, standardized test battery approaches to neuropsychological assessment are compared and contrasted within the context of advances in noninvasive technology readily available for use within the examiners office. By demonstrating the relative strengths and benefits of syndrome analysis, it is suggested that this approach provides a thorough and efficient method of neuropsychological assessment. Subsequently, the utility of an a priori hypothesis testing process approach as a critical technique in syndrome analysis will be supported. It will be proposed that QEEG procedures provide a useful method for further substantiating conclusions generated from a syndrome analysis approach to neuropsychological assessment. Two cases are described demonstrating the utility and flexibility of the QEEG as a confirmatory test of localization following syndrome analysis. In summary, the contributions that neuropsychologists make to the understanding of brain–behavior relationships may be strengthened by combining neuropsychological and neurophysiological assessment methods.