title: Modulation of striatal dopamine D1 binding by cognitive processing.
abstract: There is strong evidence that dopamine (DA) is implicated in higher-order cognitive functioning, but it remains controversial whether D1 receptor binding can be modified by cognitive activity. We examined striatal D1 binding potential (BP) in 20 younger (22-30 years) and 20 older (65-75 years) persons who underwent two [(11)C] SCH 23390 PET measurements, one while resting and one while performing a cognitive task taxing inhibitory functioning. The younger persons showed significant task-related BP reductions in sensorimotor, limbic, and associative striatum during cognitive activity compared to rest. Older persons showed no reliable BP reductions in any striatal subregion. These findings demonstrate that D1 receptor binding can be modified by cognitive activity in younger persons, but also provide novel evidence for the notion that human aging is associated not only with lower DA receptor density but also with altered modifiability of the DA system.
authors.affiliation: Aging Research Center, Karolinska Institutet, Gävlegatan 16, SE-113 30 Stockholm, Sweden. sari.karlsson@ki.se
authors.forename: Sari
authors.initials: S
authors.lastname: Karlsson
authors.forename: Lars
authors.initials: L
authors.lastname: Nyberg
authors.forename: Per
authors.initials: P
authors.lastname: Karlsson
authors.forename: Håkan
authors.initials: H
authors.lastname: Fischer
authors.forename: Petra
authors.initials: P
authors.lastname: Thilers
authors.forename: Stuart
authors.initials: S
authors.lastname: Macdonald
authors.forename: Yvonne
authors.initials: Y
authors.lastname: Brehmer
authors.forename: Anna
authors.initials: A
authors.lastname: Rieckmann
authors.forename: Christer
authors.initials: C
authors.lastname: Halldin
authors.forename: Lars
authors.initials: L
authors.lastname: Farde
authors.forename: Lars
authors.initials: L
authors.lastname: Bäckman
mesh_terms: D000328:Adult; D000368:Aged; D000375:Aging / Q000502:physiology*; D000704:Analysis of Variance; D001552:Benzazepines; D001931:Brain Mapping; D002250:Carbon Radioisotopes; D003071:Cognition / Q000502:physiology*; D003342:Corpus Striatum / Q000000981:diagnostic imaging / Q000502:physiology*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009483:Neuropsychological Tests; D049268:Positron-Emission Tomography; D017447:Receptors, Dopamine D1 / Q000378:metabolism*; D055815:Young Adult
chemical_list: D001552:Benzazepines; D002250:Carbon Radioisotopes; D017447:Receptors, Dopamine D1; C534628:SCH 23390