MarmoDetector: A novel 3D automated system for the quantitative assessment of marmoset behavior.

BACKGROUND: Callithrix jacchus, generally known as the common marmoset, has recently garnered interest as an experimental primate model for better understanding the basis of human social behavior, architecture and function. Modelling human neurological and psychological diseases in marmosets can enhance the knowledge obtained from rodent research for future pre-clinical studies. Hence, comprehensive and quantitative assessments of marmoset behaviors are crucial. However, systems for monitoring and analyzing marmoset behaviors have yet to be established. NEW METHOD: In this paper, we present a novel multimodal system, MarmoDetector, for the automated 3D analysis of marmoset behavior under freely moving conditions. MarmoDetector allows the quantitative assessment of marmoset behaviors using computerised tracking analysis techniques that are based on a Kinect system equipped with video recordings, infrared images and depth analysis. RESULTS: Using MarmoDetector, we assessed behavioral circadian rhythms continuously over several days in home cages. In addition, MarmoDetector detected acute, transient complex behaviors of alcohol injected marmosets. COMPARISON TO EXISTING METHOD: Compared to 2D recording, MarmoDetector detects activities more precisely and is very sensitive as we could detect behavioral defects specifically induced by alcohol administration. CONCLUSION: MarmoDetector facilitates the rapid and accurate analysis of marmoset behavior and will enhance research on the neural basis of brain disorders.

Cognitive impairment of Japanese multiple sclerosis patients: Follow-up study using BRB-N assessment tool.

OBJECTIVES: The purpose of this study was to evaluate cognitive function in patients with multiple sclerosis (MS), compared with control subjects, and to establish whether decline of cognitive function continues in the patients during remission. METHODS: The Japanese version of the Brief Repeatable Battery of Neuropsychological tests (BRB-N), which includes the selective reminding test (SRT), spatial recall test (SPART), symbol digit modalities test (SDMT), paced auditory serial addition test (PASAT), and the word list generation test (WLG), was performed in 34 Japanese patients with MS (8 males, 26 females; mean age, 42 years) and in 37 age- and education-matched healthy controls (20 males, 17 females; mean age, 36 years). BRB-N was conducted at intervals of two years for MS patients who remained in remission, and the cognitive changes were evaluated by comparing the results with those of the initial examination at entry into the study. RESULTS: The MS patients showed lower BRB-N scores than controls, with high significance in the SRT, SRT-D, SDMT and PASAT tests (p<0.01). The BRB-N scores of the MS patients who remained in remission were not significantly changed for at least 2 years. CONCLUSIONS: The Japanese version of the BRB-N is useful to clarify the nature of cognitive impairment in Japanese MS patients. Based on this neuropsychological assessment, we suggest that working memory and information-processing speed are key deficits. Patients who remained in remission showed little or no further impairment of cognitive functions for at least two years.

Neuroimaging of itch as a tool of assessment of chronic itch and its management.

Chronic itch is a multidimensional physical state strongly associated with emotional and cognitive aspects of suffering that causes the urge to scratch. Pathophysiology, psychological stress, and social milieu can influence itch. Here, we review brain neuroimaging research in humans that detects functional and anatomic changes in health and disease states. New data are emerging that are shaping our understanding of itch mechanisms and scratching-the behavioral response as well as the effect of treatments and brain dynamics during itch. Future developments will continue to expand our knowledge of itch mechanisms, allowing translation to clinical assessment and novel therapies focused on the brain, the final relay of itch transmission.

Quantitative assessment of gait bradykinesia in Parkinson's disease using a portable gait rhythmogram.

To quantify gait bradykinesia during daily activity in patients with Parkinson's disease (PD), we measured movement-induced accelerations over more than 24h in 50 patients with PD and 17 age-matched normal controls, using a new device, the portable gait rhythmogram. Acceleration values induced by various movements, averaged each 10 min, exhibited a gamma distribution. The mean value of the distribution curve was used as an index of the "amount of overall movement per 24h". Characteristic changes were observed in both the gait cycle and gait acceleration. During hypokinesia, the gait cycle became either faster or slower. A number of patients with marked akinesia/bradykinesia showed a reduced and narrow range of gait acceleration, i.e., a range of floor reaction forces. The results suggest that assessment of the combination of changes in gait cycle and gait acceleration can quantitatively define the severity of gait bradykinesia.