title: Dopamine Alters the Fidelity of Working Memory Representations according to Attentional Demands.
abstract: Capacity limitations in working memory (WM) necessitate the need to effectively control its contents. Here, we examined the effect of cabergoline, a dopamine D2receptor agonist, on WM using a continuous report paradigm that allowed us to assess the fidelity with which items are stored. We assessed recall performance under three different gating conditions: remembering only one item, being cued to remember one target among distractors, and having to remember all items. Cabergoline had differential effects on recall performance according to whether distractors had to be ignored and whether mnemonic resources could be deployed exclusively to the target. Compared with placebo, cabergoline improved mnemonic performance when there were no distractors but significantly reduced performance when distractors were presented in a precue condition. No significant difference in performance was observed under cabergoline when all items had to be remembered. By applying a stochastic model of response selection, we established that the causes of drug-induced changes in performance were due to changes in the precision with which items were stored in WM. However, there was no change in the extent to which distractors were mistaken for targets. Thus, D2agonism causes changes in the fidelity of mnemonic representations without altering interference between memoranda.
authors.affiliation: University of Oxford.
authors.forename: Sean James
authors.initials: SJ
authors.lastname: Fallon
authors.affiliation: University of Oxford.
authors.forename: Nahid
authors.initials: N
authors.lastname: Zokaei
authors.affiliation: University of Cambridge.
authors.forename: Agnes
authors.initials: A
authors.lastname: Norbury
authors.affiliation: University of Oxford.|John Radcliffe Hospital, Oxford, UK.
authors.forename: Sanjay G
authors.initials: SG
authors.lastname: Manohar
authors.affiliation: University of Oxford.|John Radcliffe Hospital, Oxford, UK.
authors.forename: Masud
authors.initials: M
authors.lastname: Husain
mesh_terms: D000328:Adult; D001288:Attention / Q000187:drug effects*; D000077465:Cabergoline; D004298:Dopamine / Q000502:physiology*; D018491:Dopamine Agonists / Q000494:pharmacology*; D004873:Ergolines / Q000494:pharmacology; D005260:Female; D006801:Humans; D008297:Male; D008570:Memory, Short-Term / Q000187:drug effects*; D011939:Mental Recall / Q000187:drug effects*; D017448:Receptors, Dopamine D2 / Q000819:agonists*; D013647:Task Performance and Analysis; D014796:Visual Perception / Q000187:drug effects*; D055815:Young Adult
chemical_list: D018491:Dopamine Agonists; D004873:Ergolines; D017448:Receptors, Dopamine D2; D000077465:Cabergoline; D004298:Dopamine