Poster Session 04 Program Schedule
02/15/2024
12:00 pm - 01:15 pm
Room: Shubert Complex (Posters 1-60)
Poster Session 04: Neuroimaging | Neurostimulation/Neuromodulation | Teleneuropsychology/Technology
Final Abstract #49
Toward Finding the Neural Implementation of Cognitive Reserve: A Longitudinal Analysis of Task Switching
Fatemeh Hasanzadeh, Columbia University, New York, United States
Yunglin Gazes, Columbia University, New York, United States
Christian Habeck, Columbia University, New York, United States
Yaakov Stern, Columbia University, New York, United States
Category: Cognitive Neuroscience
Keyword 1: cognitive reserve
Keyword 2: aging (normal)
Keyword 3: executive functions
Objective:
Age-related changes in brain structure and function contribute to declines in cognitive abilities including task-switching (Monsell 2003). However, some older individuals maintain higher levels of performance despite these neural changes, suggesting greater cognitive reserve (Stern 2009). Identifying the neurocognitive mechanisms underlying such resilience against age-related deterioration is critical for promoting successful cognitive aging.
In the current study, we aimed to investigate whether individual differences in task-related brain activation patterns moderate the impact of structural brain changes on executive function in aging. It was hypothesized that greater expression of specific fMRI activation patterns would confer resilience against the effects of increasing white matter hyperintensities (WMH) on task switching performance over time.
Participants and Methods:
A longitudinal analysis was conducted on 79 participants (40 females and 39 males) with the age of 65.3 ± 3.21 years involving a baseline assessment and one follow-up after 5 years. Participants underwent MRI and performed an intrinsically cued task switching paradigm described in (Gazes, Rakitin et al. 2012). Switch cost was calculated as the reaction time difference between switch and non-switch conditions. fMRI data was analyzed using ordinal trend canonical variates analysis (OrTCVA) (Habeck, Krakauer et al. 2005) to identify a coordinated pattern of increasing and decreasing activation from the non-switch to the switch condition. WMH burden was quantified from FLAIR MRI scans. A linear mixed effects model examined whether baseline OrTCVA pattern expression scores moderated the relationship between changes in WMH and switch cost over time.
Results:
Greater expression of the OrTCVA pattern activation pattern attenuated the longitudinal effect of increasing WMH burden on switch costs. Older individuals with higher pattern expression scores showed a shallower slope in the relationship between WMH burden changes and switch cost changes compared to those with lower scores. The results indicate that greater expression of the activation pattern was inversely associated with the effects of resilience against the adverse effects of structural deterioration on set switching performance. In this way, the obtained fMRI activation pattern can be considered a “neural implementation” of cognitive reserve.
Conclusions:
This study provides novel evidence that individual differences in the expression of a functional brain activation pattern can moderate the impact of longitudinal structural changes on change in cognitive performance. Older adults who exhibited greater expression of OrTCVA network while performing the task switching paradigm showed reduced effects of increasing WMH on switch costs over time. Thus, the enhanced recruitment of these functional brain networks reflects the neural implementation of greater cognitive reserve. These findings highlight the importance of examining both structural and functional neural changes to understanding cognitive reserve.
| 
