Lecture 12 & 13: Depression and Anxiety Flashcards
What is depression?
A transient mood or a clinical disorder
What are 2 key signs of depression?
- Constantly feeling down or hopeless
- Having little interest of pleasure in doing things you used to enjoy
What are treatment options for depression?
- Medication
- Psychotherapy
- PA?
In NZ, what age group is suffering the most from depression, anxiety and mental distress?
18-24 year olds
What percent of the population suffer from moderate to severe depression?
20%
What are psychological constructs for measuring mental health? (2)
Subjective measures:
- Self-report scales (e.g. beck depression inventory)
- Clinical diagnosis using DSM IV criteria for severe
What are objective measures of PA?
Accelerometer, step counts, fitness change
What are subjective measures of PA?
Self-report questionnaires (IPAQ)
What is correlational research?
Shows association between 2 variables measured at the same time
How does the chicken and egg scenario relate to the depression & PA relationship?
Some research doesn’t allow us to understand the direction of the relationship and whether it starts from mental ill health or inactivity
Mental ill-health -> inactivity
OR
Inactivity -> Mental ill-health
What is a cohort study?
Participants exposure to ‘risk factor’ (PA) assessed at baseline, incidence of illness (depression) measured at a later date. Risk exposure and illness incidence examined
How is an odds ratio read?
Higher number = higher risk (more likely to experience depression
What did the study by Harvey et al. (2018) conclude?
1 hour of exercise/week of any intensity is protective against future incidence of depression
People who did 0 hours had a ?? times greater chance of developing depressive symptoms 10 years later
1.5 times
Was there a linear relationship between increasing exercise and decreasing depression incidence?
Odds reduced as amount of exercise increased until 1.5 hours, after this pretty stable (no preventative benefit)
What are the 4 components of PA?
Frequency - How regularly?
Time - Duration?
Intensity - How hard?
Type - What form?
What are acute effects?
occur relatively quickly after exposure e.g., does one exercise session decrease depression?
What are chronic effects?
occur only after frequent exposures over a long period of time e.g., how frequently do we have to exercise to decrease depression
Why do variables need to be tightly controlled?
For external validity - will this relationship still exist in the real world?
How do RCT’s work?
- Eligible participants randomly allocated
- Two groups - Control & Intervention
- Compare
What did the RCT by Dunn et al. (2005) find?
- Higher dose = greatest benefit (Guidelines better than Lower Dose)
- No difference between frequencies (doesn’t matter how many days it’s done over)
- Overall, just about the amount of exercise, at least 3 times a week (3-5 recommended)
What have RCT’s found the most effective timeframe for an intervention is?
12 weeks or less
What have RCT’s found is the best exercise intensity for depression intervention
Moderate is recommended, studies also shown benefits of light/vigorous
What have RCT’s found is the best time per session?
Sessions over 60 minutes have similar outcomes to 30-60 min - more about total volume over the week
What forms of PA have very strong evidence for decreasing depressive symptoms?
Aerobic forms of PA, other modes (e.g., yoga, muscle strengthening) also beneficial
What works faster, medication or exercise?
Medication
Is exercise as effective as medication?
Yes just takes longer
Why would some say that exercise is more effective than medication?
Exercise has more effects on other aspects of health
Who is less likely to relapse, medication or exercise group?
Exercise group
What is qualitative research?
collecting and analyzing non-numerical data to understand concepts, opinions or experiences
What did qualitative research find were the benefits to mental health from exercising?
- Improved mood
- Better attention
- Stress management
- Positive distraction
- Sense of purpose
- Regaining pleasure
- Self-confidence
What could be some of the challenges of promoting or using PA as a means of treating depression?
- Low confidence when experiencing symptoms
- Fatigue
- Mental exhaustion
- Social withdrawal and/or anxiety
- Fear of failure and social evaluation
What is anxiety?
State of worry, apprehension or tension that often occurs in the absence of real or obvious danger - has physiological and psychological symptoms
What is state anxiety?
anxiety induced by a situation in the current moment
What is trait anxiety?
innate disposition to respond to situation with anxiety - occurs on a day to day basis
During the 2020 lockdown how many ND respondents reported moderate to high anxiety?
15.6%
In non-anxious people, higher levels of self-reported PA is associated with what?
Decreased risk of developing anxiety symptoms and anxiety disorders at least a year later
What was the anxiety and PA relationship under COVID restrictions?
Those who spent more time in moderate to vigorous PA had 15-34% lower chances of presenting anxiety symptoms
What has RCT evidence found is the best frequency of PA for reducing anxiety?
Benefits found for <150 & >150 min/wk
4-5 times/wk most effective
What has RCT evidence found is the best session time of PA for reducing anxiety?
No differences between shorter and longer sessions
What has RCT evidence found is the best intensity of PA for reducing anxiety?
Moderate-to-high intensities more effective than low
What has RCT evidence found is the best type of PA for reducing anxiety?
All modes effective; strongest effect for yoga, stretching and other mind-body exercise
According to experimental evidence, will one session of exercise make us feel less anxious?
Yes, for at least 2-4 hours post exercise, similar effects to relaxation
What is the problem with exercised based research?
people that sign up are interested in exercise and expect to change from effects hence results are more poor quality
- So choosing control group is important for reducing expectancy bias
What are neurobiological mechanisms of exercise improving anxiety and/or depression?
Produce similar changes in the brain neural systems that occur with medication
- be wary of using the “endorphin” hypothesis to explain changes
What are psychosocial mechanisms of exercise improving anxiety and/or depression?
- Self confidence
- Distraction
- Reappraisal of anxiety symptoms
