Models of Unipolar Depression

Biochemical factors

Low activity of serotonin and NR, hormones and HPA pathway

Subgenual cingulate; Irregular activity and blood flow; Interconnectivity

Brains circuits

Under intense stress, immune system dysregulation contributes to depression; Slower functioning of lymphocytes; Illnesses caused by CPR production and body inflammation

Biological view

Biological treatments

Antidepressants and brain stimulation

Antidepressants

MAO, tricyclics, second generation ADs, ketamine-based

Brain stimulation

Electroconvulsive therapy and other forms

Increases activity level of neurotransmitters serotonin and NR; Iproniazid; Tyramine

MAO inhibitors

Acts on NT reuptake mechanism of key neurons; Biological correction; Imipramine; Tofranil

Tricyclics

SSRI; Increase serotonin activity without affecting other transmitters; Fluoxetine/Prozac; Sertraline/Zoloft; Escitalopram/Lexapro

Second-gen ADs

Increases NR activity only

Atomoxetine/Strattera

Increases both serotonin and NR activity

Venlafaxine/Effexor

Increases activity of glutamate in brain; May aid in new neural pathway dev; Alleviates depression quickly, combines well, used to unresponsive or suicidal persons; Short-term impact

Ketamine-based ADs

Biological treatments that directly or indirectly stimulate certain areas of the brain

Brain stimulation

Methods of brain stimulation

ECT, VNS, TMS, and DBS

Implanted pulse generator sends electrical signals to the vagus nerve, which then delivers electrical signals to the brain; Helps reduce depression

VNS

Depression results from problematic behaviors and dysfunctional thinking

CB view

Theoretical CB perspectives

Behavioral dimension, negative thinking, complex CB factor interplay

Life rewards related to presence or absence of depression; Reduction in rewards may cause fewer positive behaviors, lower positive rewards, and eventual depression; Strong relationship between positive life events and feelings of life satisfaction and happiness

Behavioral dimension

UPD is produced by a combination of…

Maladaptive attitudes, cognitive triad, errors in thinking, and automatic thoughts

Negative view of experiences, oneself, and future

Cognitive triad

Linked to longer feelings of dejection and increased likelihood of later life clinical depression

Ruminative responses

People believe they have no control over life’s reinforcements and assume responsibility for this helpless state

Learned helplessness

Internal attribution of present lack of control → feel helpless of prevent future negative outcomes → depression

Attribution-helplessness theory

Reintroduction to pleasurable activities; Consistent reward and reward withhold; Improve social skills

CB therapy

Phase 1 of CB therapy

Increasing activities and elevating mood

Phase 2 of CB therapy

Challenging automatic thoughts

Phase 3 of CB therapy

identifying negative thinking and biases

Phase 4 of CB therapy

Changing primary attitudes

New-wave approach to CB therapy suggests individuals do not need to…

Fully discard negative cognitions to overcome depression

ACT

Acceptance and commitment therapy

UPD influenced by social context and often triggered by outside stressors

SC view