Brain, Behavior, and Self- Efficacy for Cognitive Function in Older Adults

Transcription

1 Brain, Behavior, and Self- Efficacy for Cognitive Function in Older Adults Amanda N. Szabo, B.S.*, Katherine S. Hall, M.S., Maritza Alvarado, M.S, Michelle Voss, M.S., Kirk Erikson, Ph.D. Arthur F. Kramer, Ph.D, and Edward McAuley, Ph.D.

2 Introduction Aging results reductions in: Physical function Muscle mass/ strength Balance Cognitive function: Increased Processing Speed Decreased Executive function Loss of Memory Implications for self-efficacy

3 Cardio-respiratory fitness associated with Increases in self efficacy (McAuley & Blissmer, 2000) Cognitive Function (McAuley, Kramer, Colcombe, 2004) Brain structure and activation (Kramer et al. 2006) Self-efficacy has been associated with cognitive performance Older adults lower self-efficacy and poorer cognitive performance than young adults (Artistico et al., 2003)

4 PET and fmri work suggests self-related processes associated activation in: Middle Frontal Gyrus- self reflections Anterior Cingulate- Decision making Posterior Cingulate- Recall and envisioning Precuneous- Self consciousness

5 Study Purpose To examine the contribution of activity in specific regions of the brain to self-efficacy following performance of a challenging cognitive task To determine whether any relationships were independent of known correlates of cognitive function

6 N=122 Participants Older adults (M age = 66.5 yrs; 68% female) Community dwelling and surrounding area of Champaign County in Illinois Recruited to participate in a year long exercise intervention

7 Screening Sedentary Screened for: Health conditions Right handedness Claustrophobia Metal objects Obtained physician approval

8 Measures Physical Fitness (VO2 max) Assessed through physician supervised GXT

9 Measures Self efficacy Assesses confidence for accuracy of cognitive performance (McAuley et al., 2006) 8 items reflecting beliefs in capabilities to accurately complete incremental numbers of trials on a complex cognitive task

10 Cognitive Task Paradigm Dual Task (Erickson, 2005) Responses made on a key pad Each participant under went: 48 dual trials A or B 2 3 B A 2 or 3 Each stimuli is presented for a 3 second duration, followed by a fixed ISI of 1.5 s and a variable ITI ranging from 0s to 7.5 s

11 fmri Protcol All participants completed cognitive task in a 3 Tesla MRI Both Structural and Functional Brain scans were collected

12 Procedure Day One GXT Day Two Practice Dual Task Pre-task self efficacy questionnaire fmri Post -task self efficacy questionnaire

13 fmri Analysis All data reconstruction and analysis were preformed on FSL (Smith, 2004) Lower level analysis was performed to register each participant s functional data to the structural space of each individual subject Higher-level analysis using a GLM to combine the data from all 122 subjects

14 Regions of Interest (ROIs) ROIs were selected Based on previous literature MFG Anterior Cingulate Posterior Cingulate Precuneous Greatest activation during Dual task

15 Results

16 Correlations with post dual task self efficacy Age Pre-dual task efficacy -.639** VO 2 ml/kg.255* Dual Task Error -.441** MFG % signal change.249** Anterior Cingulate % signal change.245** Posterior Cingulate % signal change.278** Right Precuneous % signal change.215* Left Precuneous % signal change.276** * p>.05, **p>.001

17 Predicting Post Dual Task Efficacy Hierarchical Linear regression predicting Mean Post Dual-task Self efficacy F= (9, 121), p<.001 R 2 =.58 Model β p R 2 Change Age Pre Dual Task Self Efficacy **.275 VO 2 in ml/kg Dual Task Error **.068 MFG % signal change **.040 Ant. Cing % signal change Post. Cing % signal change *.012 R. Precu. % signal change L. Precu. % signal change

18 Summary Support for established sources of efficacy, as well as activity in those areas of the brain associated with self reflection MFG and Posterior Cingulate were the only independent brain activity predictors of post-task self efficacy in regression analyses Support for previous research in which MFG is associated with self confidence and cognitive control (Buckner, 2007 & Overwalle, 2008) Support for Posterior Cingulate s involvement in Envisioning.

19 Conclusion One of the largest fmri studies Results are preliminary Field and measurement approaches are constantly changing Just completed 12-month trial Plan to examine associations between changes in physical activity, physical fitness, cognition, brain activity and self-efficacy

20 Thank you!