Genetic Risk Score Predicts Late-Life Cognitive Impairment

Introduction. A family history of Alzheimer's disease is a significant risk factor for its onset, but the genetic risk associated with possessing multiple risk alleles is still poorly understood. Methods. In a sample of 95 older adults (Mean age = 75.1, 64.2% female), we constructed a genetic risk score based on the accumulation of risk alleles in BDNF, COMT, and APOE. A neuropsychological evaluation and consensus determined cognitive status (44 nonimpaired, 51 impaired). Logistic regression was performed to determine whether the genetic risk score predicted cognitive impairment above and beyond that associated with each gene. Results. An increased genetic risk score was associated with a nearly 4-fold increased risk of cognitive impairment (OR = 3.824, P = .013) when including the individual gene polymorphisms as covariates in the model. Discussion. A risk score combining multiple genetic influences may be more useful in predicting late-life cognitive impairment than individual polymorphisms

Physical activity is associated with reduced Implicit learning but enhanced relational memory and executive functioning in young adults

Accumulating evidence suggests that physical activity improves explicit memory and executive cognitive functioning at the extreme ends of the lifespan (i.e., in older adults and children). However, it is unknown whether these associations hold for younger adults who are considered to be in their cognitive prime, or for implicit cognitive functions that do not depend on motor sequencing. Here we report the results of a study in which we examine the relationship between objectively measured physical activity and (1) explicit relational memory, (2) executive control, and (3) implicit probabilistic sequence learning in a sample of healthy, college-aged adults. The main finding was that physical activity was positively associated with explicit relational memory and executive control (replicating previous research), but negatively associated with implicit learning, particularly in females. These results raise the intriguing possibility that physical activity upregulates some cognitive processes, but downregulates others. Possible implications of this pattern of results for physical health and health habits are discussed

Physical activity is associated with reduced Implicit learning but enhanced relational memory and executive functioning in young adults

Accumulating evidence suggests that physical activity improves explicit memory and executive cognitive functioning at the extreme ends of the lifespan (i.e., in older adults and children). However, it is unknown whether these associations hold for younger adults who are considered to be in their cognitive prime, or for implicit cognitive functions that do not depend on motor sequencing. Here we report the results of a study in which we examine the relationship between objectively measured physical activity and (1) explicit relational memory, (2) executive control, and (3) implicit probabilistic sequence learning in a sample of healthy, college-aged adults. The main finding was that physical activity was positively associated with explicit relational memory and executive control (replicating previous research), but negatively associated with implicit learning, particularly in females. These results raise the intriguing possibility that physical activity upregulates some cognitive processes, but downregulates others. Possible implications of this pattern of results for physical health and health habits are discussed

Relationship between PA*, the three measures comprising PA* (average steps, hours of PA, and number of bouts), and explicit cognitive performance.

<p>Relationship between PA*, the three measures comprising PA* (average steps, hours of PA, and number of bouts), and explicit cognitive performance.</p

Schematic of the Triplets Learning Task.

<p> Each trial, or ‘triplet’, is comprised of two sequentially presented red cues and a green target. Participants observe the red cues and respond as quickly as possible to indicate the location of the green target. Unbeknownst to them, there is a probabilistic regularity embedded in the task, such that the first red cue predicts the target’s location with 80% probability.</p

Gender-specific relationships between PA*, each of the three PA measures (average steps, hours of PA, and number of bouts), and IL.

<p>Bolded values marked with an asterisk denote significant correlations, and bolded values without an asterisk denote marginal correlations.</p

Gender moderates the relation between PA and implicit learning.

<p>Plots depict correlations between IAL scores from the first session of training and a composite measure of PA in males (A) and females (B).</p

Relationship between PA*, the three measures comprising PA* (average steps, hours of PA, and number of bouts), and implicit learning performance.

<p>Relationship between PA*, the three measures comprising PA* (average steps, hours of PA, and number of bouts), and implicit learning performance.</p