Bruce J. Diamond

Mindfulness meditation improves cognition: Evidence of brief mental training☆

Although research has found that long-term mindfulness meditation practice promotes executive functioning and the ability to sustain attention, the effects of brief mindfulness meditation training have not been fully explored. We examined whether brief meditation training affects cognition and mood when compared to an active control group. After four sessions of either meditation training or listening to a recorded book, participants with no prior meditation experience were assessed with measures of mood, verbal fluency, visual coding, and working memory. Both interventions were effective at improving mood but only brief meditation training reduced fatigue, anxiety, and increased mindfulness. Moreover, brief mindfulness training significantly improved visuo-spatial processing, working memory, and executive functioning. Our findings suggest that 4days of meditation training can enhance the ability to sustain attention; benefits that have previously been reported with long-term meditators.

Ginkgo biloba Extract: Mechanisms and Clinical Indications

OBJECTIVE Ginkgo biloba may have a role in treating impairments in memory, cognitive speed, activities of daily living (ADL), edema, inflammation, and free-radical toxicity associated with traumatic brain injury (TBI), Alzheimers dementia, stroke, vasoocclusive disorders, and aging. The purpose of this review is to provide a synthesis of the mechanisms of action, clinical indications, and safety of Ginkgo biloba extract. DATA SOURCES Empirical studies, reviews, chapters, and conference proceedings were identified in the following databases: Medline, the Research Council for Complementary Medicine based on the British Library database, and Psychlnfo. Ginkgo biloba, EGb 761, Tanakan, Tebonin, Rokan, and LI 1370 were the principal index terms. STUDY SELECTION AND DATA EXTRACTION Controlled clinical studies with both positive and negative findings are included, in addition to animals studies illustrating mechanisms of activity. DATA SYNTHESIS Ginkgo has shown activity centrally and peripherally, affecting electrochemical, physiologic, neurologic, and vascular systems in animals and humans with few adverse side effects or drug interactions. Ginkgo shows promise in patients with dementia, normal aging, and cerebrovascular-related disorders. Clinical indications include memory, information processing, and ADL. CONCLUSIONS Ginkgo shows promise in treating some of the neurologic sequelae associated with Alzheimers disease, TBI, stroke, normal aging, edema, tinnitus, and macular degeneration. Mechanisms of action may include antioxidant, neurotransmitter/receptor modulatory, and antiplatelet activating factor properties. While safe, caution is advised when recommending ginkgo to patients taking anticoagulants. Future studies should examine dose effects, component activity, mechanisms, and clinical applications.

Speed of information processing as a key deficit in multiple sclerosis: implications for rehabilitation

Speed of information processing was assessed in patients with multiple sclerosis and healthy controls using both an auditory and visual task designed to control for accuracy of performance across groups. After controlling for accuracy of performance, patients with multiple sclerosis were found to have significantly slower speed of information processing relative healthy controls, irrespective of the modality of stimulus presentation (auditory or visual). When given an adequate amount of time to process information, however, the patients performed similarly to controls. These results suggest that persons with multiple sclerosis experience deficits specifically in processing speed but not performance accuracy. Results are discussed in terms of rehabilitative guidelines for the cognitive improvement of persons with multiple sclerosis.

Speed of information processing in traumatic brain injury: modality-specific factors.

Objective: To assess speed of information processing by two serial addition tests (one visual, one auditory) in individuals with moderate-to-severe traumatic brain injuries (TBIs) and in a healthy, normal control group (NC). The tasks were designed to equate and control for accuracy of performance across the TBI and NC groups, thus allowing for quantification of information processing speed. Design: Performance across groups and tasks were compared using 2 × 2 repeated measure analyses of variance (ANOVAs). In addition, each individuals processing speed was used to adjust rate of stimulus presentation on a subsequent “rehabilitation” trial to determine further whether this adjustment equated accuracy of performance. Setting: Rehabilitation hospital. Patients: 22 outpatients with moderate-to-severe TBI (6 women, 16 men; mean age = 34.6 years; duration of loss of consciousness = 22.6 days) and 20 age- and education-matched healthy controls. Results: Processing speed was slower in TBI subjects, relative to controls and was significantly related to measures of executive functioning for those with TBI. Relative to controls, speed of processing in the TBI group was disproportionately slower when information was presented in the auditory, relative to the visual, modality. Conclusions: Speed of information processing is a major impairment in those with TBI when unconfounded by performance accuracy. The modality-specific impairment observed in the TBI group may, in part, be due to a greater within-modality interference effect created by the auditory version of the task. By manipulating information at a pace customized for an individual through compensatory strategies and environmental modifications, information-processing performance of TBI participants can be enhanced significantly.

Working memory deficits in chronic fatigue syndrome: Differentiating between speed and accuracy of information processing

To examine the relative influence of speed of information processing versus working memory ability, CFS participants with psychiatric comorbidity (CFS-Psych) and CFS without a psychiatric history (CFS-noPsych) were examined on tests of visual and auditory processing speed and visual and auditory working memory. Compared to healthy controls (HC) and a group of participants with rheumatoid arthritis (RA), the CFS-noPsych group displayed significantly reduced performance on tests of information processing speed, but not on tests of working memory. No significant differences were observed between the CFS-Psych group and any other group in the study. The implications of group heterogeneity on the understanding of cognitive impairment in CFS are discussed.

Ginkgo biloba: Indications, Mechanisms, and Safety

Ginkgo biloba special extract (EGb761) is used in most randomized control trials. Indications include cognition and memory in Alzheimer disease, age-associated dementia, cerebral insufficiency, intermittent claudication, schizophrenia, and multi-infarct dementia. Dosages range from 80 to 720 mg/d for durations of 2 weeks to 2 years. Mechanisms of action include increasing cerebral blood flow, antioxidant and antiinflammatory effects, with antiplatelet effects attributed to flavone and terpene lactones. Possible interactions with monoamine oxidase inhibitors, alprazolam, haloperidol, warfarin, and nifedipine have been reported. Optimal dosage/duration, dose-response characteristics, drug interactions, bioavailability, long-term effects, and optimal intervention timing should be the focus of future work.

Selective Impairment of Auditory Processing in Chronic Fatigue Syndrome: A Comparison with Multiple Sclerosis and Healthy Controls

The most consistent deficit observed in individuals with Chronic Fatigue Syndrome has been in efficiency of information processing. To examine the possibility of a modality-specific impairment, the present study examined subjects with Chronic Fatigue Syndrome, multiple sclerosis, and healthy controls on an auditory-versus visual-paced serial-addition test. 20 subjects with Chronic Fatigue Syndrome, 20 subjects with clinically definite Multiple Sclerosis, and 20 sedentary healthy controls were compared. One-half of the subjects in each group were administered the Paced Auditory Serial Addition Test and the other half were administered the Paced Visual Serial Addition Test. The group with Chronic Fatigue Syndrome was differentially impaired on the auditory relative to the visual processing task. The group with Multiple Sclerosis was equally impaired on both versions of the task. The results are discussed within the framework of Baddeleys model of working memory.

Memory Dysfunction in Fatiguing Illness: Examining Interference and Distraction in Short-term Memory

This study investigated short-term memory capacity in three fatiguing illnesses: multiple sclerosis (MS); chronic fatigue syndrome (CFS); and depression (DEP) using a proactive interference (PI) and a Brown-Peterson distraction paradigm. There were no significant differences in build-up and release from PI relative to controls, although the CFS and MS groups recalled significantly fewer words overall. All three fatigue groups evidenced recall impairment after a brief distractor. Furthermore, brief distraction resulted in impaired immediate and delayed recall in the MS and CFS groups compared to controls. Results indicate that fatiguing illness groups, particularly MS and CFS, are vulnerable to limited disruption in short-term memory processing and this can affect recall.

Impaired delay eyeblink classical conditioning in individuals with anterograde amnesia resulting from anterior communicating artery aneurysm rupture.

Anterior communicating artery (ACoA) aneurysm rupture can lead to an anterograde amnesia syndrome similar to that observed after damage to the hippocampus and medial temporal lobes (MT). It is currently believed that ACoA amnesia results from basal forebrain damage that disrupts hippocampal processing without direct hippocampal damage. Converging evidence from animal studies and computational modeling suggests that qualitative differences may exist in the pattern of memory impairment after basal forebrain or MT damage. For example, animals with basal forebrain but not hippocampal damage are impaired at delay eyeblink classical conditioning (EBCC). In this study, individuals with ACoA amnesia were shown to be impaired at delay EBCC compared with matched controls; this contrasts with the spared delay EBCC previously observed in MT amnesia. This finding suggests the beginning of a possible dissociation between the memory impairments in MT versus ACoA amnesia.

Neural and physiological correlates of translation and interpreting in the bilingual brain: Recent perspectives

In translation studies, there has been a significant increase in the range of methodologies used to examine the cognitive processes underlying translation and interpreting and determine how and where these processes are represented in the brain. Some recent data gathering tools, such as eye-tracking and keyboard logging, have by now become well-established in translation process research, but others, especially those yielding direct physiological and neurological data such as neuroimaging techniques, have yet to be widely adopted. The current paper offers a summary review of some findings concerning the neurological and physiological correlates of translation and interpreting from the perspective of recent studies that have employed a diverse array of these new data-gathering techniques to investigate bilingualism, language switching, and translation.