title: Hyperfamiliarity in Dementia and Mild Cognitive Impairment.
abstract: BACKGROUND
  Hyperfamiliarity, a phenomenon in which feelings of familiarity are evoked by novel stimuli, is well described in epilepsy and the lesioned brain. Abnormality of familiarity in Alzheimer's disease (AD) and mild cognitive impairment (MCI) have also been described in the literature, but more from a neuropsychological approach perspective. Currently, there is a lack of study on the real-life experience of familiarity abnormality in dementia and MCI. Our aim was to compare the occurrence of hyperfamiliarity among dementia and MCI.
  
  
  METHODS
  We recruited 73 participants, 29 with AD, 10 with vascular dementia, 7 with MCI and 27 healthy controls, and administered a questionnaire to assess hyperfamiliarity frequency.
  
  
  RESULTS
  Hyperfamiliarity was observed in real-life in cognitive impairment, but was unrelated to its severity or underlying aetiology.
  
  
  CONCLUSIONS
  This study highlights the similar rate of occurrence of hyperfamiliarity in the daily life of individuals with cognitive impairment. Future research should examine neuropsychological correlations and mechanisms that contribute to such observations.
authors.affiliation: Department of Neurology, Singapore General Hospital, Singapore.
authors.forename: Kathryna Sh
authors.initials: KSh
authors.lastname: Kwok
authors.forename: Shahul
authors.initials: S
authors.lastname: Hameed
authors.forename: Sze Yan
authors.initials: SY
authors.lastname: Tay
authors.forename: Way Inn
authors.initials: WI
authors.lastname: Koay
authors.forename: Sharon
authors.initials: S
authors.lastname: Koh
authors.forename: Christopher
authors.initials: C
authors.lastname: Gabriel
authors.forename: Kinjal
authors.initials: K
authors.lastname: Doshi
authors.forename: Simon Ks
authors.initials: SK
authors.lastname: Ting
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000503:physiopathology / Q000523:psychology*; D016022:Case-Control Studies; D060825:Cognitive Dysfunction / Q000503:physiopathology / Q000523:psychology*; D003704:Dementia / Q000503:physiopathology / Q000523:psychology; D015140:Dementia, Vascular / Q000503:physiopathology / Q000523:psychology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D021641:Recognition, Psychology; D012720:Severity of Illness Index; D012846:Singapore