title: Effect of low-dose acute tryptophan depletion on the specificity of autobiographical memory in healthy subjects with a family history of depression.
abstract: BACKGROUND
  Low-dose acute tryptophan depletion (LD-ATD), while having no effect on mood, has been shown to reduce specificity of autobiographical memory in patients who have recovered from a depressive episode.
  
  
  OBJECTIVE
  This study aimed to explore if reduced specificity of autobiographical memory with LD-ATD is common to other groups of individuals at risk of depression, specifically a healthy population with a family history of depression.
  
  
  METHODS
  Nineteen healthy young adults with at least one first-degree relative with a history of major depression were recruited. LD-ATD drinks containing 1.15 g of tryptophan (T+) or no tryptophan (T−) were administered on two separate occasions, in a double blind random order crossover design. The Autobiographical Memory Test (AMT) was administered 5 h after drink administration.
  
  
  RESULTS
  Analysis of variance revealed a significant difference in the effects of LD-ATD drinks on plasma free tryptophan with no mood change with either drink. There was no within-subject main effect of LD-ATD on the memory task. However, there was a main effect of order of drink. Exploratory analysis of visit 1 data indicated a large between-subject effect (d=1.4) of LD-ATD on AMT with T− associated with less specificity in response to negative cue words (F(1, 17)08.71, p=0.009).
  
  
  CONCLUSIONS
  Similar to findings following recovery from depression, LD-ATD can reduce specificity of AMT in the absence of lowered mood in healthy individuals with a strong family history of depression. These findings may reflect a 5-HT-dependent cognitive vulnerability to depression in different populations and warrant further research.
authors.affiliation: Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, UK.
authors.forename: Hamid A
authors.initials: HA
authors.lastname: Alhaj
authors.forename: Matthew
authors.initials: M
authors.lastname: Selman
authors.forename: Victoria
authors.initials: V
authors.lastname: Jervis
authors.forename: Jacqui
authors.initials: J
authors.lastname: Rodgers
authors.forename: Stephen
authors.initials: S
authors.lastname: Barton
authors.forename: R  Hamish
authors.initials: R
authors.lastname: McAllister-Williams
mesh_terms: D000704:Analysis of Variance; D018592:Cross-Over Studies; D003865:Major Depressive Disorder / Q000453:epidemiology*; D004311:Double-Blind Method; D005192:Family Health; D005260:Female; D006801:Humans; D008297:Male; D061212:Memory, Episodic; D014364:Tryptophan / Q000008:administration & dosage / Q000172:deficiency*; D055815:Young Adult
chemical_list: D014364:Tryptophan