title: Differences in prefrontal cortex activation and deactivation during strategic episodic verbal memory encoding in mild cognitive impairment.
abstract: In this study we examined differences in fMRI activation and deactivation patterns during episodic verbal memory encoding between individuals with MCI (n = 18) and healthy controls (HCs) (n = 17). Participants were scanned in two different sessions during the application of self-initiated or directed instructions to apply semantic strategies at encoding of word lists. MCI participants showed reduced free recall scores when using self-initiated encoding strategies that were increased to baseline controls' level after directed instructions were provided. During directed strategic encoding, greater recruitment of frontoparietal regions was observed in both MCI and control groups; group differences between sessions were observed in the ventromedial prefrontal cortex and the right superior frontal gyrus. This study provides evidence suggesting that differences of activity in these regions may be related to encoding deficits in MCI, possibly mediating executive functions during task performance.
authors: Departamento de Radiologia, Faculdade de Medicina, Universidade de São Paulo São Paulo, Brazil ; Departamento de Neurologia, Faculdade de Medicina, Universidade de São Paulo São Paulo, Brazil.
authors: Joana B
authors: JB
authors: Balardin
authors: Departamento de Radiologia, Faculdade de Medicina, Universidade de São Paulo São Paulo, Brazil.
authors: Marcelo C
authors: MC
authors: Batistuzzo
authors: Departamento de Radiologia, Faculdade de Medicina, Universidade de São Paulo São Paulo, Brazil.
authors: Maria da Graça Moraes
authors: Mda G
authors: Martin
authors: Centro de Matemática, Computação e Cognição, Universidade Federal do ABC Santo André, Brazil.
authors: João R
authors: JR
authors: Sato
authors: Departamento de Neurologia, Faculdade de Medicina, Universidade de São Paulo São Paulo, Brazil.
authors: Jerusa
authors: J
authors: Smid
authors: Departamento de Neurologia, Faculdade de Medicina, Universidade de São Paulo São Paulo, Brazil.
authors: Claudia
authors: C
authors: Porto
authors: Department of Psychiatry and Behavioral Sciences, Center for Health Behavior Neuroscience, University of Kansas Kansas City, KS, USA.
authors: Cary R
authors: CR
authors: Savage
authors: Departamento de Neurologia, Faculdade de Medicina, Universidade de São Paulo São Paulo, Brazil.
authors: Ricardo
authors: R
authors: Nitrini
authors: Departamento de Radiologia, Faculdade de Medicina, Universidade de São Paulo São Paulo, Brazil.
authors: Edson
authors: E
authors: Amaro
authors: Departamento de Neurologia, Faculdade de Medicina, Universidade de São Paulo São Paulo, Brazil.
authors: Eliane C
authors: EC
authors: Miotto
keywords: age-related memory disorders; fMRI; mild cognitive impairment; semantic encoding; verbal episodic memory