Editing Caudate nucleus (section)

===Sleep===
Bilateral lesions in the head of the caudate nucleus in cats were correlated with a decrease in the duration of deep [[slow wave sleep]] during the sleep-wakefulness cycle.  With a decrease in total volume of deep slow wave sleep, the transition of [[short-term memory]] to [[long-term memory]] may also be affected negatively.<ref>{{cite journal | vauthors = Gogichadze M, Oniani MT, Nemsadze M, Oniani N |title=Sleep disorders and disturbances in memory processing related to the lesion of the caudate nucleus |journal=Parkinsonism and Related Disorders |volume=15 |year=2009 |pages=S167–S168 |doi=10.1016/S1353-8020(09)70639-X }}</ref>

However, the effects of caudate nuclei removal on the sleep–wakefulness pattern of cats have not been permanent.  Normalization occurs by three months after caudate nuclei [[ablation]].  This discovery may be due to the inter-related nature of the roles of the caudate nucleus and the [[frontal cortex]] in controlling levels of [[central nervous system]] activation.  The cats with caudate removal, although permanently hyperactive, had a significant decrease in [[rapid eye movement sleep]] (REMS) time, which lasted about two months.  However, afrontal cats had a permanent decrease in REMS time and only a temporary period of hyperactivity.<ref name="pmid15339255">{{cite journal | vauthors = Villablanca JR | title = Counterpointing the functional role of the forebrain and of the brainstem in the control of the sleep-waking system | journal = Journal of Sleep Research | volume = 13 | issue = 3 | pages = 179–208 | date = September 2004 | pmid = 15339255 | doi = 10.1111/j.1365-2869.2004.00412.x | doi-access = free }}</ref>

Contrasting with associations between "deep", REM sleep and the caudate nucleus, a study involving [[EEG]] and [[fMRI]] measures during human sleep cycles has indicated that the caudate nucleus demonstrates reduced activity during non-REM sleep across all sleep stages.<ref>{{cite journal | vauthors = Kaufmann C, Wehrle R, Wetter TC, Holsboer F, Auer DP, Pollmächer T, Czisch M | title = Brain activation and hypothalamic functional connectivity during human non-rapid eye movement sleep: an EEG/fMRI study | journal = Brain | volume = 129 | issue = Pt 3 | pages = 655–67 | date = March 2006 | pmid = 16339798 | doi = 10.1093/brain/awh686 | doi-access = free }}</ref>  Additionally, studies of human caudate nuclei volume in [[congenital central hypoventilation syndrome]] (CCHS) subjects established a correlation between CCHS and a significant reduction in left and right caudate volume.  CCHS is a genetic disorder that affects the [[sleep cycle]] due to a reduced drive to breathe.  Therefore, the caudate nucleus has been suggested to play a role in human sleep cycles.<ref>{{cite journal | vauthors = Kumar R, Ahdout R, Macey PM, Woo MA, Avedissian C, Thompson PM, Harper RM | title = Reduced caudate nuclei volumes in patients with congenital central hypoventilation syndrome | journal = Neuroscience | volume = 163 | issue = 4 | pages = 1373–9 | date = November 2009 | pmid = 19632307 | pmc = 2761724 | doi = 10.1016/j.neuroscience.2009.07.038 }}</ref>