Shaky scaffolding: Age differences in cerebellar activation revealed through activation likelihood estimation meta‐analysis

Abstract

Cognitive neuroscience research has provided foundational insights into aging, but has focused primarily on the cerebral cortex. However, the cerebellum is subject to the effects of aging. Given the importance of this structure in the performance of motor and cognitive tasks, cerebellar differences stand to provide critical insights into age differences in behavior. However, our understanding of cerebellar functional activation in aging is limited. Thus, we completed a meta-analysis of neuroimaging studies across task domains. Unlike in the cortex where an increase in bilateral activation is seen during cognitive task performance with advanced age, there is less overlap in cerebellar activation across tasks in older adults (OAs) relative to young. Conversely, we see an increase in activation overlap in OAs during motor tasks. We propose that this is due to inputs for comparator processing in the context of control theory (cortical and spinal) that may be differentially impacted in aging. These findings advance our understanding of the aging mind and brain.

Multiple bouts of high-intensity interval exercise reverse age-related functional connectivity disruptions without affecting motor learning in older adults

“…While the cerebellum is broadly involved in motor learning 57 – 61 , it is integral for error-based learning 58 , 62 . Age-related cortico-cerebellar FC decreases have been previously documented in older adults 63 , 64 with increased cortico-cerebellar connectivity hypothesized to contribute to more efficient sensorimotor transformations 63 , 65 . The importance of cerebellar involvement in error-based learning coupled with the widespread increases in cortico-cerebellar FC in the exercise group here suggests that exercise may affect cortico-cerebellar circuitry which may enhance error-based learning 66 , 67 .…”

“…Given the age-related disruptions in resting state networks 17 , 63 , increases in FC suggest that exercise may be an effective intervention for reversing declines in brain networks as we age. Specifically, mounting evidence suggests that the cerebellum acts as a critical structure to maintain normal motor and cognitive functioning during aging 65 , 71 . Older adults show widespread decreased connectivity between the right lobule 1–6, 10, and crus 1 of the cerebellum and the putamen 63 and decreased connectivity between the cerebellum and the medial temporal lobe 63 , 72 .…”

Multiple bouts of high-intensity interval exercise reverse age-related functional connectivity disruptions without affecting motor learning in older adults

“…Given the age-related disruptions in resting state networks 17,62 , increases in FC suggest that exercise may be an effective intervention for reversing declines in brain networks as we age. Specifically, mounting evidence suggests that the cerebellum acts as a critical structure to maintain normal motor and cognitive functioning during aging 64,70 . Older adults show widespread decreased connectivity between the right lobule 1-6, 10, and crus 1 of the cerebellum and the putamen 62 and decreased connectivity between the cerebellum and the medial temporal lobe 62,71 .…”

“…Older adults show widespread decreased connectivity between the right lobule 1-6, 10, and crus 1 of the cerebellum and the putamen and decreased connectivity between the cerebellum and the medial temporal lobe Siman-Tov et al, 2017). Additionally, the FC increases, which were limited to the right cerebellum in the older adult exercise group, are noteworthy considering that older adults display bilateral cerebellar recruitment during motor tasks (e.g., sequence learning and tapping) relative to young adults (Bernard et al, 2020). Thus, the increased couplings between limbic brain regions, the putamen, and the middle temporal gyri and the cerebellum in the exercise group suggest that repeated bouts of exercise paired with learning may contribute to enhanced cerebellar activity that could support motor and cognitive functioning in older individuals (Bernard et al, 2020).…”

“…While the cerebellum is broadly involved in motor learning Debas et al, 2010;Doyon et al, 1997;Doyon & Benali, 2005;Hikosaka et al, 2002), it is integral for error-based learning (Debas et al, 2010;Doya, 2000). Age-related cortico-cerebellar FC decreases have been previously documented in older adults Seidler et al, 2015) with increased cortico-cerebellar connectivity hypothesized to contribute to more efficient sensorimotor transformations (Bernard et al, , 2020. The importance of cerebellar involvement in error-based learning coupled with the widespread increases in cortico-cerebellar FC in the exercise group here suggests that exercise may specifically target cortico-cerebellar circuitry which may enhance error-based learning (Neva, Ma, Orsholits, Boisgontier, & Boyd, 2019;Wanner, Cheng, & Steib, 2020).…”