Search

Hiroyuki Karibe,1 Michihiko Koeda,2 Kyoko Aoyagi-Naka,1 Yuichi Kato,1 Amane Tateno,2 Hidenori Suzuki,3 Yoshiro Okubo21Department of Pediatric Dentistry, School of Life Dentistry at Tokyo, Nippon Dental University, Tokyo, Japan; 2Department of Neuropsychiatry, Nippon Medical School, Tokyo, Japan; 3Department of Pharmacology, Nippon Medical School, Tokyo, JapanPurpose: The sound of dental treatments can evoke anxiety in some dental patients. While women have shown greater dental anxiety than men, little is known about the gender differences in the perception of dental sounds. The purpose of this preliminary study was to evaluate differences in the perception of dental sounds according to the level of dental fear and gender.Patients and methods: Based on the level of dental fear, 69 adults (39 women, 30 men; average age, 28.1±8.1years) were categorized into four groups. Three types of sounds were presented to participants: two sounds associated with dental treatment and a neutral sound. All participants rated their emotional reaction to each sound on a visual analog scale.Results: Significant differences were observed for ratings of valence and disgust for a dental drilling sound among the four groups (p=0.007 and 0.004, respectively). Female participants in the dental fear group rated the dental drilling sound as more negative and disgusting than did female participants in the control group (p=0.002 for both ratings). However, no significant differences were found in ratings between males in the dental fear and control groups.Conclusion: Perception of dental sounds appears to differ by level of dental fear and by gender. Considering these differences may contribute to reducing fear in dental patients.Keywords: dental anxiety, adult, auditory stimuli, sound, visual analog scale

BACKGROUND: Peripheral benzodiazepine receptor (PBR) in the brain of Alzheimer's disease (AD) patients has been discussed in relation to the role of gliosis in AD. The PBR was shown to have the ability to reflect activated glial cells, including microglia. The role of activated microglia in AD is an important topic in the pathophysiology of AD. The aim of this study was to quantify PBR in AD brain with a new high-sensitive PBR ligand, [(11)C]DAA1106. METHODS: Positron emission tomography (PET) scans with [(11)C]DAA1106, a potent and selective ligand for PBR, were performed on 10 patients with AD and 10 age-matched control subjects. All patients had mild to moderate dementia. Duration of illness was 1-3 years at the time of the scans. The PBR binding in the regions of interest was quantified by binding potential (BP) obtained from compartmental model analysis with plasma input function. RESULTS: Mean BP was increased in the brain of AD patients compared with control subjects in all measured regions. Statistical significance reached across many of the regions examined, including dorsal and medial prefrontal cortex, lateral temporal cortex, parietal cortex, occipital cortex, anterior cingulate cortex, striatum, and cerebellum. CONCLUSIONS: The broad increase of PBR binding measured with [(11)C]DAA1106 in the brain of AD patients suggests a widespread existence of cellular reactions with PBR in relatively early-stage AD.

Selective listening is an essential auditory process that enables one to attend to the speech of a certain speaker among a mixture of parallel conversations, a phenomenon known as the cocktail party effect. Early experimental psychology in this area has long employed a so-called dichotic listening paradigm, where the subjects were typically presented with a set of monotonic tones, distinct to each ear, and were instructed to identify a target tone. The experimental setting of such a paradigm is, however, conceptually far from that we experience in daily life. Here, we instead developed an experimental paradigm based father on actual human conversation, and thereby investigated neural network underpinning the selective listening function in more realistic auditory settings. Twenty healthy volunteers (mean age 24.9 years) participated in the following experimental session, during which their cerebral hemodynamic activities were recorded by functional magnetic resonance imaging (fMRI). In a single fMRI session, the subjects were presented with auditory stimuli in one of the three conditions: (1) a news story read by a target speaker (N condition), (2) two news stories read simultaneously but independently by the target and other speaker (i.e. distracter) of an incongruent sex (Si condition), and (3) the same as (2) but sex of the distracter being congruent (Sc condition). The duration of each condition was 20 s, and the stimuli were followed by a visual presentation of a word, for which the subjects were instructed to judge whether or not the word was present in the preceding story. This train of conditions was repeated six times, and the brain activities during the Si and Sc conditions were compared with that in the N condition. We found that (a) in both Si and Sc conditions, prominent activations were observed in bilateral superior and middle temporal gyri, (b) compared to the Si condition, the activations in the Sc condition were more widespread and observed also in left inferior and middle frontal gyri, and (c) among these regions, the activities in temporal areas were positively correlated with the performance of the word challenge. Collectively, these results suggest that bilateral temporal and left frontal lobes play a key role in selective listening encountered in daily life depending on the degree of attention., 38th Annual Meeting of Society for Neuroscience

Weight gain has been identified as being responsible for increased morbidity and mortality rates of schizophrenia patients. For the management of weight gain, exercise is one of the most acknowledged interventions. At the same time, exercise and sports have been recognized for their positive impact on psychiatric symptoms of schizophrenia. However, the neurobiological basis for this remains poorly understood. We aimed to examine the effect of sports participation on weight gain, psychiatric symptoms and brain activation during sports observation in schizophrenia patients. Thirteen schizophrenia patients who participated in a 3-month program, including sports participation and 10 control schizophrenia patients were studied. In both groups, body mass index (BMI), Positive and Negative Syndrome Scale (PANSS), and brain activation during observation of sports-related actions measured by functional magnetic resonance imaging were accessed before and after a 3-month interval. BMI and general psychopathology scale of PANSS were significantly reduced in the program group but not in the control group after a 3-month interval. Compared with baseline, activation of the body-selective extrastriate body area (EBA) in the posterior temporal-occipital cortex during observation of sports-related actions was increased in the program group. In this group, increase in EBA activation was associated with improvement in the general psychopathology scale of PANSS. Sports participation had a positive effect not only on weight gain but also on psychiatric symptoms in schizophrenia. EBA might mediate these beneficial effects of sports participation. Our findings merit further investigation of neurobiological mechanisms underlying the therapeutic effect of sports for schizophrenia.