Prepulse inhibition (PPI) is considered to be one of the most promising neurophysiological indexes for translational research in psychiatry. Impairment of PPI has been reported in several psychiatric diseases, particularly schizophrenia, where PPI is considered a candidate intermediate phenotype (endophenotype) of the disease. Recent findings from a variety of research areas have provided important evidence regarding PPI impairment. Human brain imaging studies have demonstrated the involvement of the striatum, hippocampus, thalamus and frontal and parietal cortical regions in PPI. In addition, several genetic polymorphisms, including variations in the genes coding for Catechol O-methyltransferase, Neuregulin 1, nuclear factor kappa-B subunit 3 and serotonin-2A receptor were related to PPI; and these findings support PPI as a polygenetic trait that involves several neurotransmitter pathways. Early psychosis studies suggest that PPI disruption is present before the onset of psychosis. Also, discrepancy of PPI impairment between children and adults can be found in other psychiatric diseases, such as autistic spectrum disorders and posttraumatic stress disorder, and comprehensive investigation of startle response might contribute to understand the impairment of the neural circuitry in psychiatric diseases. Finally, recent studies with both Asian and Caucasian subjects indicate that patients with schizophrenia exhibit impaired PPI, and impaired sensorimotor gating might be a global common psychophysiological feature of schizophrenia. In conclusion, studies of PPI have successfully contributed to a better understanding of the fundamental neural mechanisms underlying sensorimotor gating and will certainly be most valuable in devising future approaches that aim to investigate the complex pathogenesis of psychiatric diseases.
Adult ; Asian Continental Ancestry Group ; Catechol O-Methyltransferase ; Catechols ; Child ; Clinical Coding ; Endophenotypes ; Hippocampus ; Humans ; Mental Disorders ; Neuregulin-1 ; Neuroimaging ; Neurotransmitter Agents ; Phenotype ; Polymorphism, Genetic ; Psychophysiology ; Psychotic Disorders ; Schizophrenia ; Sensory Gating ; Startle Reaction ; Stress Disorders, Post-Traumatic ; Thalamus ; Translational Medical Research

Results: In the early phase after surgery, 71% and 43% of the participants were nonindependent ambulators at 1W and 2W, respectively. Histopathology indicated that patients with solid tumors (ependymoma, astrocytoma, or lipoma) showed significantly lower indices at 1W and 2W than those with vascular tumors (hemangioblastoma or cavernous hemangioma). Regarding tumor location, thoracic cases exhibited poorer lower-limb function at 1W and 2W and poorer walking ability at 2W than cervical cases. According to the receiver operating characteristic (ROC) analysis, 2 WISCI II points at 2W had the highest sensitivity (100%) and specificity (92.2%) in predicting the level of walking independence at 1 year postoperatively (the area under the ROC curve was 0.99 (95% confidence interval, 0.93–1.00). Conclusions The higher the lower-limb function scores in the early phase, the better the improvement in walking ability is predicted 1 year after ISCT resection.

Methods: Eighty patients who underwent surgical resection at Keio University and Fujita Health University in Tokyo, Japan between 2003 and 2015 with more than 2 years of follow-up were enrolled. A good surgical result was defined as an improvement in the modified McCormick Scale score by one grade or more or having the same clinical grade as was observed preoperatively. Meanwhile, a poor result was defined as a reduction in the McCormick Scale score of one grade or more or remaining in grade IV or V at final follow-up. Univariate and multivariate logistic regression analyses of the following factors were performed in the two groups: sex, age, preoperative Visual Analog Scale (VAS), tumor location, the extent of tumor resection, hemosiderin caps, cavity length, and tumor length on magnetic resonance imaging. Results: At final follow-up, 15 patients were included in the poor results group and 65 in the good results group. In the univariate analysis, the factors related to poor results were as follows: higher age, preoperative McCormick Scale score severity, higher preoperative VAS, thoracic location, hemosiderin capped, and non-gross total resection (GTR). A multiple logistic regression analysis was conducted and showed that age, worse preoperative McCormick Scale score, and non-GTR were significant factors for poor prognosis. Conclusions The independent risk factors for motor deterioration after ependymoma resection were age, worse preoperative McCormick Scale score, and non-GTR. Early surgery for patients with even mild neurological disorders could facilitate functional outcomes. These results may contribute to determining the optimal timing of surgery for spinal intramedullary ependymoma.

The purpose of the present study was to examine the associations of replacing accelerometer-measured sedentary behavior (SB) with physical activity (PA) and depression in a sample of Japanese frail older adults using an Isotemporal Substitution (IS) model. Among 139 frail older adults, accelerometer was utilized to identify the daily average time spent in SB, light-intensity PA (LPA), and moderate- to vigorous-intensity PA (MVPA). Depression was assessed using the Geriatric Depression Scale-Short Version-Japanese (GDS-S-J). The relationship between SB, LPA, and MVPA with depression was examined with three models of multiple regression analysis: single factor model, partition model, and IS model. As results, LPA times was negatively associated with GDS-S-J scores in the single factor model (B = -0.09, p = 0.007) and the partition model (B = -0.13, p < 0.001). In the IS model, replacement of 10 minutes of SB with an equal amount of LPA time showed a significant negative association with GDS-S-J scores (B = -0.09, p=0.003). These results suggest that replacing a small amount of SB with LPA may be associated with an improvement in depression in frail older adults.