memory enhancement and exercise

Question 1

hippocampus and neurogenesis

Answer 1

• hippocampus is important for relational memory
  
  • effects of physical activity and fitness have been shown in hippocampus
  • undergoes neurogenesis beyond gestational period

Question 2

where does neurogenesis occur?

Answer 2

hippocampus, specifically dentate gyrus

Question 3

enriched environment (rats)

Answer 3

neurogenesis:
- enriched environment rats had significantly more new neurons in dentate gyrus than control group, also had more baby neurons

memory:
- enriched environment rats performed better in Morris Water Maze due to new neurons

Question 4

exercise (rats)

Answer 4

neurogenesis: (4 groups: CG, EE, run, EE and run)
- run group gained more neurons than other groups
* rats who ran more had more neurogenesis

memory:
- run group vs. control group
* run group performs better in path length (distance traveled) and time (how long they take to get to platform)
* run group spent more time in platform quadrant

Question 5

rodent models show that aerobic exercise helps with

Answer 5

• neurogenesis
• memory performance
• angiogenesis
• synaptogenesis
• decreases brain inflammation

Question 6

neurogenesis and humans

Answer 6

• Methods available to measure neurogenesis in humans are limited
• Can infer neurogenesis via combining data from rats and humans and using neuroimaging techniques

Question 7

exercise and hippocampus in older adults (Erickson et al 2011)

Answer 7

Participants:
- exercise group –> aerobic walking
- stretching group –> yoga, resistance training

Findings: (after 6 months)
1. structural MRI, assess hippocampal volume
- hippocampus size: EG increased, stretching decreased

2. fitness test, VO2 max
   
   • more improved fitness leads to more growth in hippocampus
3. memory task
   
   • individuals that saw a larger change in hippocampus, saw larger improvements

(1 year later)
- aerobic exercise group saw increase in hippocampal volume
- increase in volume correlated with:
* increase in memory performance
* increase in fitness level

Question 8

exercise and hippocampus in children (Chaddock et al. 2010)

Answer 8

Participants:
- lower-fit children
- higher-fit children

Findings: (cross-sectional study)
- HFC had larger hippocampi than LFC
- hippocampal volume correlates with relational memory performance
- hippocampal volume does NOT correlated with item memory performance
- hippocampal volume MEDIATES the relationship between fitness and relational memory

Question 9

aging and hippocampus

Answer 9

hippocampus remains relatively stable across young/middle adulthood

then shrinks

Question 10

exercise and relational memory in young adults (Baym et al., 2014)

Answer 10

Participants:
- 68 healthy young adults

Findings:
- aerobic fitness level correlated with relational memory performance
- aerobic fitness level does NOT correlate with item memory performance

Question 11

magnetic resonance elastography

Answer 11

measure mechanical properties of tissue by sending non-invasive shear wave to brain

Question 12

Exercise and Hippocampus in YA (Swcharb et al., 2017)

Answer 12

Participants:
- 51 healthy YA

Findings: (cross-sectional study)
- aerobic fitness level correlates with hippocampal viscoelastic measures of tissue integrity
- hippocampal viscoelasticity correlate with relational memory performance
- hippocampal viscoelasticity MEDIATE relationship between fitness and memory

Question 13

western diet and hippocampal memory (Molteni et al., 2002; rats)

Answer 13

Participants:
- High-Fat Refined Carbon-Hydrate/ Sucrose Diet group (HFS)
- Low-Fat Complex Carbon-Hydrate Diet group (LFCC)

Morris Water Maze task:
- LFCC takes almost half of their time in platform quadrant, HFS do not take nearly as much time
- HFS do worse over time than other rats

–> LFCC diet is better than an HFS diet

Question 14

dietary lipids and relational memory (Baym et al., 2014; children)

Answer 14

Participants:
- 52 children

Findings: (based on self-reported measures)
- children that had higher Omega-3 intake perform better in relational memory task
- children with higher saturated fat perform worse in relational memory task

–> good fats lead to better relational memory performance and bad fats lead to worse relational memory performance

Question 15

cartenoids and relational memory (Hassevort et al., 2017; children)

Answer 15

• more fitness, less errors
• children with more mascular Leutin make less errors than children who have less mascular Leutin

Question 16

dietary choices that impacts relational memory – NEGATIVE findings

Answer 16

• diets high in saturated fat result in poorer hippocampal-dependent spatial navigation in rodent models
• children who consumed more saturated fats perform poorer on relational memory tasks

Question 17

dietary choices that impacts relational memory – POSITIVE findings

Answer 17

• children who consume more Omega-3 fatty acids perform better on relational memory tasks
• children with higher levels of mascular Leutin perform better on relational memory tasks

Question 18

In what ways are newly generated hippocampal cells similar to existing hippocampal cells?

Answer 18

• similar dendritic length and spine density
• no significant differences between cell types on: resting potential, spiking threshold, or firing rate