Depression and Bipolar

Question 1

Mood Disorders

Answer 1

• Known as affective disorders
• Primarly disorders of mood rather than thought
• Two key emotions on the continuum: depression and mania
• Unipolar depression: only depression
• Bipolar disorder: mania that alternate with periods of depression

Question 2

Depression Prevalence

Answer 2

• 17% of adults experience depression (women more than men)

- Approx 50% of ppl will recover in 6 weeks and 90% within a year

Question 3

Suicide

Answer 3

• Between 6 and 15% of those with severe depression commit suicide
• Over 1 million people commit suicide each year
• Senior citizens have the highest rate of suicide of all age groups

Question 4

Depression: 5 main areas of functioning

Answer 4

• Emotional symptoms: feeling miserable, empty, lack of pleasure
• Motivational symptoms: lacking drive, initiative, spontaneity
• Behavioural symptoms: less active, productive, loss/gain appetite, sleep disturbances
• Cognitive symptoms: hold negative view of themselves, pessimism
• Physical symptoms: headaches, general ache and pain

Question 5

Diagnosing Unipolar Depression

Answer 5

• DSM-IV Criteria for Major Depressive Disorder
  Criteria 1: Major depressive episode
• Marked by 5 or more symptoms eg depresison mood or irritable, change in sleep/activity
• Present nearly everyday lasting two or more weeks
  Criteria 2: NO history of mania

Question 6

Cause of Depression: Biopsychosocial Model

Answer 6

1. Psychological
2. Biological
3. Social

Question 7

Causes of Depression: genetic factors

Answer 7

• Studies suggest some people have inherit a biological predisposition
• AS many as 20% of relatives of those with depression also have depression themselves, compared to less than 10% of the general population
• Twin studies demostrate a strong genetic component (concordance rates for identical twins = 46%)
• May be tied to specific genes eg. 5-HT transporter gene

Question 8

Causes of Depression: brain anatomy

Answer 8

Brain anatomy and circuits

• Researchers have determined that emotional reactions of various kinds are tied to brain circuits
• circuit responsible for unipolar depression has begun to emerge
• likely areas involved include: perfrontal cortex, hippocampus, amydala, subgenual cingulate, brain steam

Question 9

Causes of Depression: Biochemical factors

Answer 9

• clinical depression is associated with neurochemical alterations in the brain
• main biological theory of depression is the monoamine hypothesis first proposed in 1965
• Endocrine system/hormone release: people with depression have been found to have abnormal levels of cortisol
• People with depression have been found to have abnormal melatonin secretion (difficult sleeping)

Question 10

Monoamine Hypothesis

Answer 10

• Monoamines: include 5-HT, dopamine, NA and A
• Depression is associated with a deficiency in the neurotransmitters NA and 5HT
• Seratonin is more assoicated with mood
• NA is more associated with motor activity

Question 11

Evidence for Monoamine Hypothesis

Answer 11

• many drugs that enhance the activity of NA and seratonin will elevated mood (and conversely, drugs that decrease the activity of NA or 5HT will depress mood)
• Genetic studies linking 5HT transporter gene

Question 12

Evidence against Monoamine Hypothesis

Answer 12

• Studies aiming to show changes in monoamine pathway activity are largely negative
• Amphetamines and cocaine do not have an antidepressant effect
• Antidepressant medications boost monoamine levels immediately but therapeutic effect is delayed by weeks

Question 13

Antidepressant Drugs

Answer 13

• Main types:
• MAO Inhibitors: increases cytosolic stores of NA or 5HT
• Monoamine (NA and 5HT) reuptake inhibitors: tricyclic antidepressants (first generation) and SSRIs (second generation)

Question 14

Monoamine Oxidase (MAO) Inhibitors

Answer 14

• Slows down the body’s production of MAO
• MAO breaks down monoamines
• MAO inhibi stop this breakdown from occuring
• This leads to a rise in NA activity
• About half of patients who take these drugs are helped by them
• SE: blood pressure may rise to a potentially fatal level is one eats food with tyramine (cheese, banana and wine) while take MAOIs

Question 15

Tricyclics

Answer 15

• Tricyclics block the reuptake process, thus increasing NT activity in the synapse
  Strong evidence:
• 60-65% of patients find symptom improvement

Question 16

Second-generation Antidepressants

Answer 16

• SSRIs: structurally diff from MAOI and tricyclics
• Only act on 5HT
• as effective as tricyclics but clinicians prefer because it is harder to overdose and there are no dietary restrictions and fewer side effects

Question 17

Schizophrenia

Answer 17

• ‘Split mind’ - actually refers to a split from reality
• Schizophrenia spectrum disorders
• Characterised by disorganised thinking, emotions and behaviours that are disparate with their situations
• Disturbed perceptions, including delusions and hallucinations

Question 18

Pschyosis

Answer 18

• A state defined by a loss of contact with reality
• the ability to perceive and respond to the environment is significantly disturbed; functioning is impaired
• Symptoms may include hallucinations and/or delusions
• Psychosis may be substance-induced or caused by brain injury, but most appear in the form of schizophrenia

Question 19

Schizophrenia: Symptoms

Answer 19

Three categories:

1. Positive symptoms
   - pathological additions to a person’s behaviour e.g. delusions, hallucinations, disordered thinking
2. Negative symptoms
   - pathological deficits to a person’s behaviour e.g. blunted/flat affect, loss of volition, social withdrawal
3. Psychomotor/disorganised symptoms:
   - awkward movements, repeated grimaces, add gestures ( can be extreme = catatonia)
   - Disorganised speech

Question 20

Course of Schizophrenia

Answer 20

Three phases:

1. Prodromal: beginning of deterioration, mild symptoms
2. Active: symptoms become increasingly apparent
3. Residual: a return to prodromal levels, 1/4 recover, 3/4 continue to have residual symptoms

Question 21

Diagnosis: Schizophrenia

Answer 21

• DSM-IV
• Symptoms persist for 6+ months
• Type I: dominated by positive symptoms (may be more closely linked to biochemical abnormalities in the brain)
• Type II: dominated by negative symptoms (may be tied to structural abnormalities in the brain)

Question 22

What causes Schizophrenia

Answer 22

Biological View:

1. Diathesis-Stress Model:
   - Combination of biological and genetic vulnerabilities (diathesis) and environmental stress (stress) that both contribute to the onset of Schizophrenia
2. Biological Vulnerabilities
   - Genetic factors
   - Brain abnormailities
   - Biochemical abnormalities

Question 23

Schizophrenia: genetic factors

Answer 23

• Family pedigree studies: Schizophrenia is more common among relatives of people with the disorder
• first degree relatives = 10%

Question 24

Schizophrenia: Brain structure

Answer 24

Abnormal brain structure

• radiological evidence- enlarged ventricles
• Smaller temporal lobes and abnormal BF to certain areas of brain
• Overactivity of thalamus and amygdala

Question 25

Schizophrenia: Biochemical abnormalities

Answer 25

Dopamine Hypothesis - theory attricutes symptoms of Schizophrenia to disturbed and hyperactive dopaminergic signal transduction - certain dopamine neurons fire too often - particularly common in type I

Question 26

Dopamine Hypothesis evidence

Answer 26

FOR: - antipsychotic medications which acts as antagonists of DA D2 receptors - Extra DA receptors have been noted in the brains of Schizophrenia patients - PD patients can develop Schizophrenia symptoms if they take too much L-Dopa AGAINST: - atypical antipsychotics also bind to D1 and 5HT receptors - only seems to explain type I Schizophrenia

Question 27

Schizophrenia: Treatments

Answer 27

- Primarily antagonists of DA D2 receptor - reduces symptoms in 65% of patients - produce the maximal level of improvement in the first 6 months of treatment

Question 28

Antipsychotic Drugs: SEs

Answer 28

- disturbing movement problems: most common is similar to PD eg. tremour and muscle rigidity - Tardive dyskinesia

Question 29

Bipolar: Diagnosis

Answer 29

- Criteria 1: manic episode (3 or more symptoms of mania lasting one week or more) - criteria 2: history of mania - if currently experiencing hypomania or depression Types: 1. Bipolar I disorder: full manic and major depressive episodes 2. Bipolar II disorder: hypomanic episodes and major depressive episodes

Question 30

Causes of Bipolar

Answer 30

1. genetic factors 2. brain structure abnormalities 3. ion transport abnormalities 4. biochemical abnormalities

Question 31

Bipolar: genetic

Answer 31

- children of a bipolar parents face 8-25% chance | - a number of SNPs and genes have been associated with increased risk of bipolar eg. CACNA1C

Question 32

Bipolar: brain structure

Answer 32

- Basal ganglia and cerebellum

Question 33

Bipolar: ion transport

Answer 33

- may cause neurons to fire too easily (mania) or too stubbornly (depression)

Question 34

Bipolar: NTs

Answer 34

Permissive theory: - Low 5HT may 'open the door' to a mood disorder and permit NA to define the particular form the disorder will take - low 5HT + low NA = depression - low 5HT + high NA = mania

Question 35

Bipolar: treatments

Answer 35

- lithium and other mood stabilisers