title: Biological aspect of hyperthymic temperament: light, sleep, and serotonin.
abstract: BACKGROUND
  Hyperthymic temperament is one of several premorbid temperaments putatively associated with bipolar disorder. Several reports suggest that depressive patients with hyperthymic temperament may belong to the proposed soft bipolar spectrum.
  
  
  OBJECTIVE
  To investigate biological aspects of hyperthymic temperament, the present study examined daily activity, sleep time, central serotonergic function, and other relevant variables in relation to hyperthymic temperament in healthy subjects.
  
  
  METHODS
  Fifty six healthy subjects were monitored via the actigraphy system to measure daily total activity, sleep time, and illuminance. A neuroendocrine challenge test was performed to estimate central serotonergic function.
  
  
  RESULTS
  Multiple regression analysis revealed that higher illuminance of daytime, greater fluctuation in sleep time, and lower central serotonergic function significantly and independently predicted hyperthymic temperament scores.
  
  
  CONCLUSIONS
  The present findings suggest that light, sleep, and serotonin are crucial factors in understanding hyperthymic temperament, which may be common to bipolar disorder.
authors.affiliation: Department of Neuropsychiatry, Oita University Faculty of Medicine, Yufu City, Oita, Japan.
authors.forename: Nobuhiko
authors.initials: N
authors.lastname: Hoaki
authors.forename: Takeshi
authors.initials: T
authors.lastname: Terao
authors.forename: Yumei
authors.initials: Y
authors.lastname: Wang
authors.forename: Shinjiro
authors.initials: S
authors.lastname: Goto
authors.forename: Kounosuke
authors.initials: K
authors.lastname: Tsuchiyama
authors.forename: Noboru
authors.initials: N
authors.lastname: Iwata
mesh_terms: D056044:Actigraphy; D000328:Adult; D003527:Cyclothymic Disorder / Q000378:metabolism*; D005260:Female; D006801:Humans; D008027:Light; D008297:Male; D012044:Regression Analysis; D012701:Serotonin / Q000378:metabolism*; D012890:Sleep; D013997:Time Factors; D055815:Young Adult
chemical_list: D012701:Serotonin
references.citation: Curr Opin Psychiatry. 2010 Jan;23(1):12-8
references.pmid: 19809321
references.citation: Bipolar Disord. 2002 Dec;4(6):347-56
references.pmid: 12519094
references.citation: Psychopharmacology (Berl). 2003 Apr;167(1):97-102
references.pmid: 12601506
references.citation: Br J Psychiatry. 1978 Nov;133:429-35
references.pmid: 728692
references.citation: Biol Psychiatry. 2000 Sep 15;48(6):593-604
references.pmid: 11018230
references.citation: Sleep. 2007 Apr;30(4):519-29
references.pmid: 17520797
references.citation: Bipolar Disord. 2005 Apr;7(2):176-86
references.pmid: 15762859
references.citation: Behav Ther. 2009 Jun;40(2):131-41
references.pmid: 19433144
references.citation: Am J Psychiatry. 2005 Apr;162(4):656-62
references.pmid: 15800134
references.citation: J Affect Disord. 2008 May;108(1-2):11-23
references.pmid: 17950467
references.citation: J Affect Disord. 2006 Apr;91(2-3):125-31
references.pmid: 16464506
references.citation: Psychopharmacol Bull. 1987;23(1):68-73
references.pmid: 3602332
references.citation: Aggress Violent Behav. 2008 Oct;13(5):383-395
references.pmid: 19802333
references.citation: J Clin Psychol. 2009 Oct;65(10):1071-86
references.pmid: 19670448
references.citation: Clin Neuropharmacol. 1993;16 Suppl 3:S6-18
references.pmid: 8131155
references.citation: Clin Psychol Rev. 2006 Oct;26(6):679-94
references.pmid: 16904251
references.citation: Psychiatr Clin North Am. 1999 Sep;22(3):517-34, vii
references.pmid: 10550853
references.citation: Psychopharmacology (Berl). 2007 Feb;190(2):213-9
references.pmid: 17072588
references.citation: Biol Psychiatry. 1997 Jun 15;41(12):1165-73
references.pmid: 9171907
references.citation: Genes Brain Behav. 2008 Nov;7(8):869-76
references.pmid: 18826446
references.citation: J Clin Psychiatry. 1998;59 Suppl 20:22-33;quiz 34-57
references.pmid: 9881538
references.citation: Psychiatry Res. 2006 Jan 30;141(1):103-14
references.pmid: 16360217
references.citation: J Affect Disord. 2005 Mar;85(1-2):85-92
references.pmid: 15780679
references.citation: Arch Gen Psychiatry. 1988 Oct;45(10):948-52
references.pmid: 3048226
references.citation: Acta Psychiatr Scand. 1999 May;99(5):315-23
references.pmid: 10353446
references.citation: Prim Care Companion J Clin Psychiatry. 2000 Feb;2(1):16-19
references.pmid: 15014663
references.citation: J Affect Disord. 2001 Sep;66(1):1-11
references.pmid: 11532527
references.citation: J Affect Disord. 2009 Jan;112(1-3):19-29
references.pmid: 18455241
references.citation: J Affect Disord. 2008 Jul;109(1-2):157-63
references.pmid: 18191458
references.citation: J Affect Disord. 2008 Jun;108(3):291-6
references.pmid: 18053580
references.citation: Br J Soc Clin Psychol. 1967 Dec;6(4):278-96
references.pmid: 6080235
references.citation: Psychopharmacology (Berl). 2004 Nov;176(3-4):407-11
references.pmid: 15160263
references.citation: Psychopharmacology (Berl). 2006 Sep;187(4):526-7
references.pmid: 16830129
references.citation: Psychiatry Res. 1996 Mar 29;60(2-3):177-84
references.pmid: 8723308
references.citation: Adv Biochem Psychopharmacol. 1995;49:99-112
references.pmid: 7653337