Depression and Exercise Flashcards
how people with depression feel, behave and think
- > have many feelings such as, hopelessness, isolation, anxiety, sadness, guilt, self-loathing (self-criticism)
- > more hours laying in bed gathering energy to do things
- > little hours spent doing things
- > exhausted and can’t be helped by sleep
- > spends little time enjoying “good days” and most time worrying how long it will last
WHO statistics - depression
- > affects about 121 million people worldwide
- > 13% of Americans experience major depression over the course of their lifetime
- > about 7% suffer from a major depressive disorder in any given year
- > fewer than 25% of those affected have access to effective treatment
- > women experience depression more than men
- > depression is the leading cause of disability (measured by years lived with disability, YLD)
- > the fourth leading contributor to the global burden of disease (GBD—the sum of years of potential life lost due to premature mortality and the years of productive life lost due to disability)
- > By 2030 it is expected to be the 2nd leading cause of disease burden worldwide behind HIV/AIDS
affect disorder family
- > anxiety
- > depression
- > mood
concept of mood
specific short-term feeling states or emotional tones which can be either positive or negative
concept of anxiety
unpleasant feeling state and psychological reaction that occurs when fear is provoked by threat
-> trait vs state anxiety
state vs trait anxiety
state anxiety: response to threatening situations
trait anxiety: from personality and how they feel about a situation
concept of depression
a state that occurs from a preception of an important loss or the threat of such a loss
-> characterised by avoidance, withdrawal, diminished activity
how are mental disorders diagnosed?
- > no biological test currently available
- > diagnosis comes from mental health specialists
diagnostic and statistical manual of mental disorders DSM-V
(American Psychiatric Association)
- > Medical experts have established 2 core and 9 other symptoms for depression (four psychological and five physical)
- > To have depression, a person must have at least 1 of the core symptoms and 5 or more of the other symptoms present in the same two week period within the last month
core symptoms of depression
- > depressed mood most of the day, nearly everyday
- > diminished interest in pleasure in all or almost all activities most of the day, nearly everyday
other symptoms of depression
- > feeling guilty, hopeless and worthless
- > recurring suicidal thoughts
- > having trouble sleeping, either too much or too little
- > experiencing appetite/weight changes
- > trouble concentrating
- > feeling little energy or unexplained tiredness
- > agitation or slowing down of body movement
other types of depression
bipolar disorder - alternating episodes of emotional highs (mania) and lows (depression)
dysthymia - mild depression symptoms that last two years or longer
postpartum depression - a type of depression that occurs in the mother after her baby is born
seasonal affective disorder (SAD) - a major depression that occurs during seasons with low sunlight
co-existing conditons with depression
- > Anxiety disorders
- > Alcohol and/or substance abuse
- > Heart disease
- > Stroke
- > Cancer
- > HIV/AIDS
- > Diabetes
- > Parkinson’s disease
beck depression inventory
Used to assess presence and intensity of depressive symptoms in psychiatric populations – Self-report
– 21 items
– Symptoms & attitudes common to depression
– Scored 0-3 for intensity (3 = highest)
– Summed to give total score
<10 = none/minimal depression
10-18 = mild/moderate depression
19-29 = moderate/severe depression
30-63 = severe depression
Center for Epidemiologic Studies Depression Scale
Used to assess presence and intensity of depressive symptoms in the general population
– Self-report
– 20 items
– 6 domains of symptoms
– Scored 0-3 from “rarely” to “all the time”
– Summed to give total score
– ≥16 = depression
Hamilton Rating Scale for Depression (Hedlung & Vieweg, 1979)
- Self report
- 21 items (0 to 4 scale)
- Depressed mood, feelings of guilt, suicide, insomnia, work and activities, psychomotor retardation, agitation, anxiety (psychological and somatic), libido, hypochondriasis, loss of weight, insight, diurnal, paranoid, obsessional and compulsive symptoms
neurotransmitter serotonin on depression
serotonin controls mood
in some people who are severely depressed, receptors may be insensitive to serotonin
or the message of serotonin can be weakened if the originating cell releases too little of serotonin
or if an overly efficient reuptake occurs where serotonin doesn’t get much of a chance to bind to the receptors
mood-linked responses in medial frontal cortex in patients with depression
- > using functional magnetic resonance imaging (fMRI), 16 patients with depression were presented with sad movie clips while taking pictures of their brain activity
- > over the next year and half 9/16 had severe depression and were compared with the other that remained healthy and people who never had depression
- > the severe depression group had more frontal region of the brain (medial prefrontal gyrus)
- > responses in this frontal region were also linked with rumination and tendency to think obessively about negative events
brain atrophy
- > depression can be associated with the loss of volume in parts of the brain, namely the hippocampus, which belongs to the limbic system (emotional centre)
- > hippocampus is important in the consolidation of information from short-term memory to long-term memory
- > the more severe the depression the more loss of brain volume
hormonal imbalance of depressed people
-> since depressed people are constantly under stress, their cortisol levels are very high consistently which isn’t good for brain volume for the hippocampus
hypothalamic-pituitary-adrenal (HAP) axis
- > environmental stressor stimulates hypothalamus and releases corticotropin releasing hormone
- > this binds to a receptor on the anterior pituitary that releases adrenocorticotropic hormone
- > adrenocorticotropic hormone binds to the receptors of the adrenal glands and stimulates the release of cortisol
how does translocator protein density relate to depression?
PET scan use a radiopharmaceutical technique that binds to a translocator proteins found in activated microglia cells
- activated microglia cells cause imflammation
microglia are a type of glial cell that are the resident macrophages of the brain and spinal cord, and thus act as the first and main form of active immune defense in the central nervous system
macrophages are a type of white blood cell that engulfs and digests cellular debris, foreign substance, microboes
- > inflammation is the body’s immune response to infection and trauma
- > one theory is that depressed patients may have been exposed to an infection or trauma, and their brain has yet to cool off from the experience
study of translocator protein density
- major depressive episode patients had more translocator protein density, which means more neuroinflammation
translocator density vs hamilton depression rating scale
- > translocator density had a linear relationship with the Hamilton Depression Rating Scale (HDRS)
- > the more translocators, the higher depression symptoms in the Hamilton Depression Rating Scale
what is a limitation of the study of depression and brain inflammation?
-> unable to determine whether the neuroinflammation occurs before depression or because of it
implications of depression and brain inflammation
- > brain inflammation, specifically microglia activation (causing more elevation translocator proteins) is implication in major depressive episode
- > suggests that treatments should be designed to reduce microglia activation in depressive patients
white and grey matter in brain
- > CNS has grey matter and white matter
- > grey matter which has pinkish-grey colour in the living brain, cotains cell bodies, dendrites and axon terminals of neurons, where the synapses are
- > white matter is made of axons connecting different parts of grey matter to each other
depression and white matter of the brain (whalley)
- > depression has been shown to alter the structure of the brain’s white matter, which allows brain cells to communicate with each other and underpins brain function
- > researchers used a diffusion tensor imaging (DTI) to map white matter structure in participants
- > participants had reduced white matter
- > limitation is that the participants were screened for depression based on self-reported symptoms and not a interview using formal criteria
genetics in depression
- > depression tends to run in families, so reseachers believe it could be genetics
- > if someone has a parent or sibling with major depression, that person probably has a 2 or 3 times greater risk of developing depression (20%-30%) compared with the average person (10%)
- > if one twin developed depression, the other twin also suffered from depression in 46% percent of identical twins, compared to 20% of fraternal twins
5-HTT gene and depression
- > 5-HTT helps regulate serotonin
- > there are 2 forms of the 5-HTT gene, the long and short
- > an individual can inherit 2 copies of the long form, 2 of the short or one of each
- > the short version is not as effective in controlling the serotonin flow as the long version
- > researchers focused on subjects who had traumatic life events over a five year period
- > patients with at least one copy of the short form of 5-HTT were more at risk of depression (33% diagnosed with depression after experiencing 4 traumatic events)
- > patients with only the long 5-HTT gene were more resistant to depression (17% diagnosed with depression after experiencing 4 traumatic events)
environment and depression
-> stressful events such as the loss of a loved one, a major life change, serious illness, have been known to trigger depression
individual differences (personality) and depression
- > pessimistic - attribution style (internal, stable, and global) - hopeless
- > optimistic - attributional style (external, unstable, and specific) - hopeful
- > shy, people who are often this way due to having been bullied or humiliated in their early years, see social interactions as threatening
- > hypersensitive to judgement of others, respond by sleeping more and craving foods
- > self-focused, who are hostile and volatiles, blame others when things go wrong and prioritise their own needs. when depressed they tend to show a “short fuse” and create collateral damage for those around them
- > perfectionists who are prone to self-criticism and a loss of pride. they may also have a limited range of adaptive strategies to stress
