Related Experiment Video
Updated: Jul 11, 2026

Association Between Sleep Quality and Cognitive Symptoms in Patients with Major Depressive Disorder
Published on: April 26, 2024
Decrease in myocardial 123I-MIBG radioactivity in REM sleep behavior disorder: two patients with different clinical
Takuya Oguri1, Naoko Tachibana, Shigehisa Mitake
1Human Brain Research Center, Kyoto University Graduate School of Medicine, Shogoin, Sakyo, Kyoto 606-8507, Japan. toguri@kuhp.kyoto-u.ac.jp
Abstract:
Although decrease in myocardial iodine-123 metaiodobenzylguanidine ((123)I-MIBG) radioactivity has been reported in patients with rapid eye movement (REM) sleep behavior disorder (RBD), its pathophysiology has not been thoroughly disclosed. We report two RBD patients with differing clinical progression, in whom myocardial (123)I-MIBG scintigraphy was performed. One 69-year-old patient had more than a 20-year history of idiopathic RBD and showed a decrease in myocardial (123)I-MIBG radioactivity. The other 69-year-old patient started to manifest nocturnal behaviors at age 62, then mild parkinsonism at age 68, and showed a similar decrease in myocardial (123)I-MIBG radioactivity both before and after the onset of parkinsonism. These cases suggest that RBD could develop in diverse patterns of clinical progression even if signs of underlying Lewy body pathology are uniformly indicated.
Related Concept Videos
REM Sleep Behavior Disorder
RBD is significantly associated with...
Management of Insomnia
Sedatives and Hypnotics Drugs: Miscellaneous Agents
Melatonin congeners like ramelteon (Rozerem) and tasimelteon (Hetlioz) selectively bind to melatonin receptors (MT1 and MT2) and thus mimic the actions of melatonin, a hormone that regulates sleep-wake cycles. Tasimelteon is primarily used for non-24-hour sleep-wake disorder, common in blind patients. They are also used to treat conditions like insomnia...
Sleep-Wake Cycles
NREM Sleep
NREM sleep comprises four progressive stages that seamlessly merge:
