Conclusions: Increased TST/DAR and decreased stage 2 latency in the music condition indicate that brief music stimulation resulted in the enhancement of parasympathetic nervous system activation. However, greater subjective sleepiness and blunted responsiveness were also observed after napping, indicating that participants experienced deeper sleep after listening to music. As this may have resulted in severe sleep inertia, future studies should aim to determine the appropriate nap time based on the conditions of the intervention. Neurological Sleep Disorders Affecting Sleep SLEEP DISORDER AND EPILEPSY: COMORBIDITY OR RELATED CONDITIONS N. Okujava 1 , A. de Weerd 2 , A. Tsereteli 1 . 1 SEIN-SKUH Epilepsy and Sleep Centre, Tbilisi State Medical University, Tbilisi, Georgia; 2 Clinical Neurophysiology and Sleepcenter, Stichtig Epilepsie Instellingen Nederland (SEIN), Zwolle, Netherlands Introduction: The mutual influence between epilepsy and sleep is seldom taken into account in clinical practice, although its impact may be important. The prevalence of sleep disorders in patients with epilepsy is estimated as two- to threefold in adults when compared with controls. In children this factor maybe even higher. A new aspect is the effect of treating the sleep disorder and vice-versa. For the latter some reports point to the effect of Vagal nerve Stimulation on respiration during sleep. Except for one or two studies in small groups of patients with obstructive sleep apnea as co-morbidity to their epilepsy, nothing is known about the effect of treating the sleep disorder on the epilepsy in the same patient. As a third line center dedicated to epilepsy and sleep disorders we have the possi- bility to study these mutual aspects. Materials and methods: Clinical evaluation, night sleep video-EEG monitoring with simultaneous sleep recording. Results: Patient JvH, male, born 30.03.1989. Complaints: restless sleep, snoring and sleepy during daytime, seizures during the night (tonic generalized, along with "small movements"). Normal findings at exami- nation except for 140 kg body weight. Diagnostic problem: frontal lobe epilepsy (FLE), parasomnia or both? Possibility of the obstructive sleep apnea syndrome (OSAS) as a comorbidity? Other possibilities for the ap- neas during or outside the seizures? Epilepsy and sleep monitoring revealed FLE with tonic seizures accompanied by apneas due to the tonic contraction of (respiratory) muscles, along with severe OSAS. Conclusions: The case study demonstrates coexistence of two different apnea types and epileptic seizures during sleep in same patient: one type of apnea is caused by seizures, while another (OSAS) exists as a comor- bidity, being an example how important knowledge of possible influences between epilepsy and sleep disorders can be. REM Behavior Disorders A STUDY IN 184 CONSECUTIVE IDIOPATHIC REM SLEEP BEHAVIOR DISORDER PATIENTS IN A SINGLE JAPANESE CENTER M. Okura , H. Sugita, Y. Fujii, R. Maeyama, K. Itoga, M. Taniguchi, M. Ohi. Sleep Medical Center, Osaka Kaisei Hospital, Osaka, Japan Introduction: REM sleep behavior disorder (RBD) is characterized by the loss of the normal REM sleep skeletal muscle atonia, resulting in complex motor behaviors associated with dream mentation. Several lines of evi- dence indicate that idiopathic RBD (iRBD) is usually a manifestation of the prodromal stages of Parkinson disease (PD), dementia with Lewy bod- ies(DLB), or multiple system atrophy(MSA). The polysomnographical hallmarks of RBD include tonic/phasic loss of the skeletal muscle atonia of REM sleep (REM sleep without atonia; RWA). Clinical risk factors for conversion from iRBD to PD, DLB and MSA are important clues in order to establish strategy for neuroprotective trials against synucleinopathy. The aim of this study was to investigate clinical and PSG characteristic of Japanese patients with iRBD. Materials and methods: The subjects were patients who came to Osaka Kaisei Sleep Medical Center, Osaka, Japan between June 2010 and May 2013. The diagnosis of RBD was made based on the International Classi- fication of Sleep Disorders 3rd edition criteria (history of dream-enacting behaviors and video-polysomnography). In our RWA scoring based on The AASM Manual for Scoring 2.3, increased EMG activity was counted separately according to the EMG activity patterns; tonic EMG, phasic pattern, and combined EMG activities. If chin EMG activity was present for more than 50% of each 30-second epoch, that epoch was scored as tonic. Phasic EMG density was scored from the chin EMG and represented the percentage of 3 second mini-epochs containing EMG activity lasting 0.1 to 5 seconds. RWA epochs includes tonic, phasic and combined (tonic þ phasic) type. We calculated the percentage of RWA, tonic REM, phasic and REM density. Results: RBD was diagnosed in 206 patients (68.4±7.0 years old). Patients with neurological condition or taking antidepressants at the initial visit and those with inadequate PSG data were excluded from this study. One hundred eighty four patients were diagnosed as iRBD. There were 139 men and 45 women with a mean age of 68.4 ±6.7 years. The mean value of the proportions of RWA as a percentage of REM sleep was 49.9± 27.7%. The mean values of tonic REM percentage (30sec) , phasic EMG activity (3sec) and any activity (3sec) during REM sleep were 35.8±28.8%, 28.8±13.3% and 49.4 ±24.8%, respectively. We confirmed that six patients converted to DLB. Conclusions: Percentage of tonic REM in Japanese patients with iRBD was lower than previously reported results from Western countries. Further studies with longitudinal assessment and testing thresholds in different race populations will reveal risk factors for neurodegeneration in iRBD. Other SLEEP TIME AND IN-PATIENT PHYSICIAN PERCEPTION OF CARE O. Olaoye. Ascent Sleep and Weight Center, Sugar Land, United States Introduction: In 2000, the Institute of Medicine estimated that almost a 100,00 people die each year from medical errors mostly in the hospital setting. Cognitive performance during a period of sleep loss is directly related to length of time awake as well as circadian time with tasks most affected by sleep loss including those that are long and monotonous such as an 8 or 12hr In-Patient Physician shift. For adults, adequate sleep time is between 7 to 9hrs. In this study, we conducted a survey amongst In-Patient Physicians regards how their sleep time affects perception of care provided. Materials and methods: We surveyed practicing In-Patient Physician across 4 mid-western states in the US in varying settings. Respondents completed a 5-page survey with 43 questions related to type of shift (7-on 7-off days,nights, other), timing of shift and patient load per shift. Sleep characteristics as well as perceived impact of sleep time on medical de- cision making were asked. Results: 200 surveys were sent through emails and 21(10%) were returned. Of the respondents, 15 were males and 6 were females.12(57%) were on days only, 3(14%) nights only and rest were days and nights. Average sleep time was < 7hrs(62%) and 7-9hrs(38%) in the 24hrs preceding a shift start. 15(75%) respondents reported feeling sleeping during their shift. For those respondents sleeping less than 7hrs, 30% felt it affected making a correct diagnosis most of the time, 50% felt it led to medication errors and communicating with patients and family while 70% said affected completing their task on time. Conclusions: Reducing medical errors in the hospital setting requires that frontline providers such as In-Patient Physicians are able to self-identify po- tential contributors to errors. Reduced sleep time is perceived by In-Patient Physicians to impact on the quality and safety of care provided to patients. Basic Research FUNCTIONAL SPECIALIZATION DIFFERENTIALLY MODULATES INFORMATION FLOW BETWEEN SINGLE NEURONS IN NREM SLEEP ACROSS SPATIO-TEMPORAL SCALES U. Olcese , J. Bos, M. Vinck, L. van Mourik-Donga, C. Pennartz. Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, Netherlands Introduction: Studies performed at the macroscopic level indicate a breakdown in cortical effective connectivity during NREM sleep [1]. Far less is known about the neuron-level mechanisms behind this phenome- non. Moreover, recent studies challenge the notion that neuronal communication is homogeneously modulated during NREM sleep (e.g. [2,3]). Here we aimed to understand how information flow between single Abstracts / Sleep Medicine 40 (2017) e186ee363 e245