Task 6 - Mood Disorders Flashcards
Major Depressive Disorder (MDD)
Mental health condition characterized by persistent feelings of sadness, loss of interest or pleasure in activities, and a range of emotional, physical, and cognitive symptoms that significantly impact daily life functioning
DSM-5 Criteria for Major Depressive Disorder
A.Five or more of a list of symptoms have been present during the same 2-week period. At least one of the symtoms should be 1) depressed mood or 2) loss of interest/pleasure
B. Cause significant distress
C. Not attributable to substance or other mdeical conditions
D, Is not better explained by other mental disorders
E. There has never been a manic or hypomanic episode
Depression with Anxious Distress
Subtype
Characterized by prominent anxiety symptoms alongside depressive symptoms.
Depression with Mixed Features
Subtype
Meeting criteria for MDD while having at least three symptoms of mania but not a full manic episode.
Depression with melancholic features
Subtype
Emphasizes prominent physiological symptoms of depression.
Depression with Psychotic Features
Subtype
Involves delusions and hallucinations related to depressive themes or unrelated/mixed themes.
Depression with Catatonic Features
Subtype
Presents with catatonic behaviors ranging from immobility to agitation.
Depression with Atypical Features
Subtype
Identified by a unique set of symptoms, not necessarily unusual.
Depression with Seasonal Pattern (Seasonal Affective Disorder, SAD)
Subtype
Depressive episodes linked to seasonal changes, specifically light exposure.
Depression with Peripartum Onset
Subytpe
Occurs during pregnancy or within 4 weeks post-childbirth, sometimes involving manic episodes.
Premenstrual Dysphoric Disorder
Subtypes
Separate from MDD, characterized by severe distress and mood swings during the premenstrual phase
Comorbid disorders of MDD
More than 70% with MDD or persistent depressive disorder have other psychological disorders like substance abuse, anxiety, or eating disorders
Genetic factors of Depression
- Studies suggest a potential role of the serotonin transporter gene in depression.
- Abnormalities in this gene might affect serotonin regulation, impacting mood stability.
- Recent meta-analysis supports the interaction between the serotonin transporter gene and early stress in predicting later depression.
Caspi et al.: Influence of Life Stress on Depression
- 5-HTT gene may not be directly associated with depression, but it could moderate the serotonergic response to stress
- Demonstrates that the gene-by-environment (GxE) interaction extends to the natural development of depression in a representative sample of humans.
- Moderation of life stress on depression was specific to a polymorphism in the 5-HTT gene, and this effect was observed regardless of the individual’s MAOA gene status
Role of Neurotransmitters in MDD
- Norepinephrine, serotonin, and to a lesser extent, dopamine, are associated with depression.
- These neurotransmitters are highly concentrated in the limbic system, linked to sleep, appetite, and emotions.
Structural and Functional Brain Abnormalities in MDD
Prefrontal Cortex: Reduced metabolic activity and gray matter volume, mainly on the left side.
Anterior Cingulate: Altered activity in response to stress and emotional expression.
Hippocampus: Reduced volume and metabolic activity in people with major depression.
Amygdala: Enlargement and increased activity seen in mood disorders.
The HPA axis
Definition
Hypothalamic-pituitary-adrenal axis:
* A complex interrelated system in the body responsible for regulating the body’s response to stress.
* It involves the hypothalamus, pituitary gland, and adrenal glands, coordinating the release of hormones like cortisol to manage stress reactions and maintain balance within the body.
Role of the HPA axis in Depression
- Individuals with depression exhibit elevated cortisol and CRH levels.
- Chronic hyperactivity in the HPA axis contributes to difficulty returning to normal after stress
- Chronic stress exposure can disrupt neuroendocrine systems, leading to HPA axis overreaction to stressors later in life.
- This overreaction alters brain neurotransmitter functioning, potentially causing depression.
Salivary Cortisol
Way to measure activity of the HPA Axis
Potential Reasons for Sex Difference in MDD
- Women’s susceptibility to depression often linked to hormonal changes.
- Ovarian hormones (estrogen, progesterone) affect neurotransmitter systems influencing mood.
- Fluctuations in estrogen and progesterone levels during pregnancy, postpartum, and menstruation can impact mood.
Learned Helplessness Theory
Emphasizes uncontrollable negative events as triggers for depression
Aaron Beck’s Cognitive Triad
Concept
Individuals with depression perceive themselves, the world, and the future negatively.
Reformulated Learned Helplessness Theory
Concept
Focuses on how attributions for negative events influence mental states. People who habitually attribute negative events internally, stably, and globally tend to blame themselves, expect more negative events, and perceive a lack of control.
Attribution theories
Concept
Theories of depression which suggest that people who are likely to become depressed attribute negative life events to internal, stable and global factors
Hopelessness Theory
Concept
Arises when individuals attribute significant life events pessimistically and feel incapable of coping with the outcomes
Ruminative Response Styles Theory
Concept
Focuses on how dwelling on negative feelings without addressing their causes contributes to depression.
Biases in Attention and Memory
Concept
Depressed individuals tend to fixate on negative stimuli and struggle to disengage from them and showcase a bias toward negative memories.
Interpersonal difficulties in MDD
- Deficits in social skills
- Need for approval and rejection sensitivity
- Excessive Reassurance Seeking
- Resultant Behaviors
Sociocultural Factors of MDD
- Cohort effects: Historical and cultural changes might elevate the risk of depression in more recent generations compared to older ones
- Gender Differences: WOmen more susceptible
- Ethnicity/Race Differences
Bipolar I Disorder
Definition
Features manic episodes leading to depressive episodes.
Bipolar II Disorder
Involves hypomania (milder form of mania) and major depressive episodes.
Cyclothymic Disorder
Definition
Shows chronic, less severe alternation between hypomanic and depressive symptoms.
Rapid Cycling Bipolar Disorder
Definition
Experiences frequent mood episodes within a year
Disruptive Mood Dysregulation Disorder (DMDD)
Definition
Severe and frequent temper outbursts inconsistent with developmental levels; requires multiple outbursts in different settings over a specific duration.
(Added because of difficulties diagnosing children with Bipolar)
Structural and functional brain abnormalities in Bipolar Disorder
Irregularities in:
* Amygdala
* Prefrontal Cortex
* Hippocampus
* Striatum
Circuits out of those could cause symptoms, possibly something to do with reward sensitivity
Neurotransmitters involved in Bipolar Disorder
- Monoamine neurontransmitter are implicated
- Dysregulation in Dopamine systems connected to reward seeking (high in manic episodes, low in depression)
Ketamines effect in treating depression
Krystal et al.
- Was thought to help in cortico-limbic pathology of depression
- Blocks GluN2B-containing NMDA receptors, influencing phosphorylation, BDNF levels, and AMPA receptor movement to synapses, enhancing connectivity
Mood stabilizers for Bipolar disorder
Mainly lithium, anticonvulsants and atypical antipsychotics
Brain Stimulation methods for Bipolar Disorder
- Repetitive Transcranial Magnetic Stimulation (rTMS)
- Vagus Nerve Stimulation (VNS)
- Deep Brain Stimulation (DBS)
Repetitive Transcranial Magnetic Stimulation (rTMS) for Depression
- Uses high-intensity magnetic pulses targeted at specific brain structures.
- Focuses on the left prefrontal cortex with low metabolic activity in some depressed individuals.
Vagus Nerve Stimulation (VNS) in Depression
- Stimulates the vagus nerve via a surgically implanted electronic device, akin to a pacemaker.
- Influences areas like the hypothalamus and amygdala involved in depression.
Deep Brain Stimulation (DBS)
- Involves surgically implanting electrodes in specific brain areas, connected to a pulse generator under the skin.
- Small-scale trials demonstrate promise in alleviating treatment-resistant depression.
Interpersonal therapy for depression
IPT identifies four main problems prevalent in depressed individuals and teaches them techniques to cope with them:
* Grief and Loss
* Interpersonal Role Disputes
* Role Transitions
* Interpersonal Skill Deficits
Effects of psychotherapies for Depression in adults
Cuijpers et al.
- Overall response rate of 56%
- Remission rate of 46%
- Improvement rate of 66%
- Type of psychotherapy used did not significantly impact the effectiveness of treatment.
Common factors in psychotherapy outcomes
Cuijpers et al.
- Therapeutic alliance
- Patient expectations
- Credibility of the treatment
- Setting and Context