Brain structure and cognitive ability in healthy aging: a review on longitudinal correlated change

Abstract

Little is still known about the neuroanatomical substrates related to changes in specific cognitive abilities in the course of healthy aging, and the existing evidence is predominantly based on cross-sectional studies. However, to understand the intricate dynamics between developmental changes in brain structure and changes in cognitive ability, longitudinal studies are needed. In the present article, we review the current longitudinal evidence on correlated changes between magnetic resonance imaging-derived measures of brain structure (e.g. gray matter/white matter volume, cortical thickness), and laboratory-based measures of fluid cognitive ability (e.g. intelligence, memory, processing speed) in healthy older adults. To theoretically embed the discussion, we refer to the revised Scaffolding Theory of Aging and Cognition. We found 31 eligible articles, with sample sizes ranging from n = 25 to n = 731 (median n = 104), and participant age ranging from 19 to 103. Several of these studies report positive correlated changes for specific regions and specific cognitive abilities (e.g. between structures of the medial temporal lobe and episodic memory). However, the number of studies presenting converging evidence is small, and the large methodological variability between studies precludes general conclusions. Methodological and theoretical limitations are discussed. Clearly, more empirical evidence is needed to advance the field. Therefore, we provide guidance for future researchers by presenting ideas to stimulate theory and methods for development.

Disentangling the Effects of Processing Speed on the Association between Age Differences and Fluid Intelligence

“…Therefore, they may reflect age-related differences in certain anterior brain regions associated with motor planning and response preparation that are also reflected in ERP latencies occurring later in the stream of information-processing such as the P3. This interpretation is supported by previous cross-sectional findings showing that anterior brain regions such as the prefrontal cortex follow a last-in-first-out pattern (Oschwald et al 2019;Sowell et al 2004) and play a substantial role in response preparation processes (Lee et al 1999;Picard and Strick 1996). Finally, this association may reflect that participants' performance on the intelligence test was affected by time restrictions, as older participants may have needed more time to check response options and may therefore have had less time to solve subsequent problems.…”

Predicting future cognitive decline from non-brain and multimodal brain imaging data in healthy and pathological aging

“…While most previous predictive studies used structural brain imaging alone, integrating structural and functional imaging has been shown to improve predictions. Since both brain structure (Oschwald et al, 2019) and brain function (Liem et al, 2020) change in aging, the most accurate predictions of brain-age have come from combining them (Engemann et al, 2020; Liem et al, 2017). Multimodal gains have also been shown in more complex predictions such as current diagnosis in AD (Rahim et al, 2016) and conversion from MCI to AD (Dansereau et al, 2017; e.g., Hojjati et al, 2018).…”

It’s About Time: Towards a Longitudinal Cognitive Neuroscience of Intelligence

“…Our goal in this chapter is to examine longitudinal studies that study change in both cognitive function and brain structure in childhood, adolescence and early adulthood, when change in both domains is rapid. A similarly exciting question is neurocognitive ageing at the other end of the lifespan -However, as that has recently been comprehensively reviewed (Oschwald et al, 2019), this chapter will focus on the period from early childhood to early adulthood. We will focus (with some partial exceptions) on studies that measure both cognitive ability and measures of brain structure on at least two time points.…”

“…In other words, it is crucial that we investigate not just how brain measures are associated with changes in intelligence in childhood, adolescence and early adulthood, but also the mirroring patterns in later life decline. A recent review (Oschwald et al, 2019) has provided a comprehensive overview of truly longitudinal investigations of age-related decline in cognitive ability and concurrent changes in brain structure. We will here summarize the key findings in the realm of intelligence specifically, but refer the reader to that resource for a more in-depth discussion of the key papers in this field.…”