lesson 11 Flashcards
depression
- depressed mood,
- Loss of interest or pleasure
- Significant weight loss or gain
- Psychomotor agitation
- Fatigue or loss of energy
- Feeling of worthlessness or excessive
guilt - Diminished ability to think, concentrate
or make decisions - Recurrent thoughts of death
- Suicidal ideation or suicide attempt
anxiety
- Feeling apprehensive
- Feeling powerless
- Sense of impending danger
- Increased heart rate, breathing
- Sweating
- Trembling
- Feeling weak or fatigued
Prevalence of mental health issues
In 2013, an estimated 3 million Canadians (11.6%)
aged 18 years or older reported that they had a mood
and/or anxiety disorder at time.
etiology of depression
- Genetics- heritable
- Prenatal factors- genetic, epigenetic, enviornmental
- Cognitive / learning styl- genetic, epigenetic, enviornmental
- Parental depression*- genetic, epigenetic, enviornmental
- Family relationships- Sociocultural Environment
- Stressful life events- Sociocultural Environment
mental health comorbidies
- 25% of adult population
struggling with mental health at
any given time - 68% of these also have coexisting medical conditions (of
which 58% of the total population
are suffering)
psychiatric diagnoses are more common among those with ‘Western’ diseases
risk factors of mental health diseases
childhood adversity;
- loss
- abuse and neglect
- household dysfunction
stress
- adverse life events
- chronic stessors
SES
- poverty
- neighbourhood
- social support
- isolation
hormones
Mood and stress are regulated by hormones:
-
Cortisol: Stress hormone; acute stress helps, chronic stress harms.
-adrrenaline: instant release fight or flight hormone, muscles tighten, energy sent to limbvs, increased sensitivity to pain - Serotonin: Mood stabilizer; mostly produced in the gut.
- Dopamine and Endorphins: Reward and pleasure.
HPA axis
Central to stress response; overactivation linked to depression and anxiety.
Gut-brain axis highlights the role of the microbiome in mood regulation.
neuroendocrinology
study oof cnnectioins between nervus and endocrine system, links essential to our wellbeing
hypothalamic-pituitary-adrenal axis
Stress and Adrenal response
* Stress hormones are produced through the actions of the Hypothalamic-Pituitary-Adrenal axis
* Elevated cortisol associated with HPA axis dysregulation
how harmful is stress
- Short-term effects of cortisol are positive – bursts of energy, heightened memory – regulation of bodily function can be life-saving
- Long-term elevation, can be debilitating, lowered immunity, bone density, muscle mass, depression
gut-brain axis and microbiome
serottnin regulates mood, and 90% is made within the gut by endocrine cells, where is regulates bowel function, microbes in the gut also stimulate serotoniin production
depression and discordance
In this ‘mismatch’ model,
* people living in affluent industrialized
societies live increasingly stressful lives,
* working long hours
* long commutes
* juggling work and family
* struggling to find time for exercise,
eat well
= stress, stress-related diseases
evlutionary explanations for depression
Evolutionary explanations for mental health
* Origins may be more general characteristics of our species, NOT ‘western’ disease
* Genetics associations – may have evolved from normal ‘advantageous’ emotions, or those that may be beneficial in less extreme form
Similarly…
* Emotions may make us feel bad, but
benefit our genes:
* signal to stop striving and conserv energy (slow down, do not waste)
* a motivator to ‘shift strategies’ to escape a bad situation
* above may work in combination
* Over active: ‘fight or flight’ mechanisms, or ‘alarm signals’ may cause anxiety disorders
if our brains are modular
- they may be adapted to specific types of tasks
- lifetime experience may determine how the modules work and relate to one another
- may predispose us to anxiety and mood
‘disordersv
Trier Social Stress Test (TSST)
subjects asked to deliver a motivated performance task in front of an audience
Hypothalamic-pituitary-adrenal axis dysregulation (high cortisol levels)
associated with cognitive dysfunction,
and increased risk for mild cognitive
impairment and Alzheimer’s disease
(AD).
* Higher cortisol levels associated with
cognitive decline in both healthy and Alzheimer’s patients
* Faster decline in Alzheimer’s patients
alzheimers disease
- Caused by abnormal buildup of proteins (amyloid-β, and Tau) which cause plaque and protein ‘tangles’ around brain cells
- Because it affects people late in life, may be an example of ‘accumulated mutations’ - therefore, thought to be ‘outside’ of the realm of natural selection’
E4 variant of APOE gene is strong predisposing factor
Grandmother Hypothesis
suggests that human females evolved to live longer than necessary for reproduction because their extended lifespan, post-menopause, allows them to help their daughters raise their children, thereby increasing the survival and reproductive success of their grandchildren and, in turn, their own genes
antagonistic pleiotropy
a theory in evolutionary biology, suggests that genes can have beneficial effects early in life, enhancing reproductive success, while also causing detrimental effects later, contributing to the aging process
APOE-E4 may be involved in
- preventing spontaneous abortion
- reducing cardiovascular responses to stress
- preventing liver damage from hepatitis
ppathology/cause of alzheimers
Thought to be caused by amyloid-β (Aβ)
plaques Tau (PHFtau) neurofibrillary tangles.
New and controversial perspectives suggest
they may be neutral by-products or even
adaptative rather than harmful lesions.
evolutionary perspectives on mental health
- Mismatch Theory:
Humans evolved for small, cooperative groups, not modern industrial societies.
Modern life creates chronic stress, isolation, and unrealistic social expectations.
- Adaptive Theories of Depression:
Depression may have evolved to conserve energy or signal social withdrawal.
May elicit help or prompt behavioral change.
- Cultural Specificity:
Cultural interpretations shape how symptoms are expressed and understood (e.g., “sinking heart” in South Asian communities).
Need to avoid over-reliance on adaptationist explanations — not all traits are evolutionary solutions.
