Age-Related Changes in the Prefrontal Cortex Associate with Loss of Memory
This research delves into age-related changes that are linked to the deterioration of working memory. While the study is conducted on mice, the results align with observations in other species. Understanding how neural circuits function provides valuable insight into the aging brain. However, it is important to note that this is just one piece of the puzzle, and there are various other factors, such as proteomic or transcriptomic changes, cell behavior, and molecular damage, that contribute to the aging process. Piecing together these different aspects to form a comprehensive understanding of cognitive aging is a complex challenge.
Cognitive aging is a natural decline in cognitive function as people age, presenting a significant challenge to quality of life and employment. Therefore, it is crucial to gain a detailed understanding of the neurobiology underlying cognitive aging. The decline in working memory is a fundamental aspect of cognitive aging and is among the earliest cognitive deficits associated with aging. Executive function is also susceptible to the effects of aging, and this study aims to shed light on how aging impacts the circuit-level computations underlying executive function using calcium imaging and optogenetic manipulation. The findings demonstrate alterations in working-memory coding and the relevant recurrent connectivity in the mouse medial prefrontal cortex (mPFC) as early as middle age.
Additionally, population activity in the mPFC exhibits distinct yet overlapping patterns between tactile and auditory modalities in young adults, enabling crossmodal memory coding alongside modality-dependent coding. However, these patterns notably diminish in middle age and further decline in advanced age. Resting-state functional connectivity, especially among memory-coding neurons, decreases in middle age, indicating compromised recurrent circuits for memory maintenance. The study’s findings provide insights into the functional alterations of the prefrontal circuit that emerge in middle age and worsen as a hallmark of cognitive aging.
Link: https://doi.org/10.1038/s41467-023-43142-0
