Brain Bee Chapter 12 - Psychiatric Disorders

psychiatric environmental factors

negative - death, poverty, addiction, exposure to violence
protective - strong support systems, coping skills, physical activity, involvement in activities

anxiety disorders

PTSD, OCD, panic attacks
most common mental disorders in America

anxiety disorder medications

→ selective serotonin reuptake inhibitors (SSRIs) raise serotonin levels, known to be deficient in psych disorders
→ benzodiazepines (diazepam, Valium) boost levels of GABA (inhibitory neurotransmitter), acting like a break pedal & decreasing brain activity in anxious patients
* risk of dependence for benzos, no longer first choice for treatment

OCD symptoms

obsessive compulsive disorder
obsessions → uncontrollable, recurring thoughts
compulsions → repeated, ritualistic behaviors to relieve the obsessions

OCD brain regions

basal ganglia → habit center of brain & involved with reward system (dopamine), feeling good (serotonin), learning and memory (glutamate)

→ disrupted signaling between basal ganglia and cortex = ritualistic behavior

OCD treatment

limited relief from meds → SSRIs at higher dosage than with depression patients
more severe → tricyclic antidepressant clomipramine or neuroleptic drugs (tranquilizers)

cognitive behavioral therapy
deep brain stimulation (DBS)

neuroleptic drugs

tranquilizing, used in severe OCD patients

DBS

deep brain stimulation
first used for Parkinson’s, now used for other psych disorders

electrodes implanted in certain brain regions emit electrical pulses intended to reset abnormal neuronal firing

panic disorder symptoms

sudden, unexpected bouts of intense, irrational fear
difficulty breathing, racing heart, sweating, dizziness

= panic attacks, last several minutes +

panic disorder treatment

psychotherapy
medications → SSRIs are primary drug, benzodiazepines used in emergency situations

PTSD cause

post-traumatic stress disorder
caused by harrowing, traumatic event

PTSD symptoms & treatment

flashbacks, nightmares, intrusive memories, hyperarousal
memory loss, feelings of blame, decreased interest in day-to-day

- cognitive behavioral therapy is most effective
- drugs that block norepinephrine (blood pressure med. prazosin & beta-blocker propranolol)
- SSRIs
- neuropeptide Y for protection against PTSD development
- drugs to target neuronal function in affected brain regions → cannabinoids, glutamate, oxytocin

PTSD physiological changes

increased heart rate and heightened electrical sensitivity when interacting with triggering stimuli
shallow sleep with increased REM periods → sleep deprivation
stress response is maximized → cortisol and norepinephrine are heightened
low levels of serotonin

PTSD nerobiological signatures

smaller hippocampus (region for learning and memory)
smaller PFC (controls thinking, emotions, behavior)
overactive amygdala (emotional center)

certain genes affect PTSD risk (also affect depression, anxiety, and panic disorder risk)

mood disorders

major depression & bipolar disorder

major depression criteria

(at least 4 must be met)
feeling empty or sad
loss of appetite
irritability
problems with sleep
changes in appetite or weight

depression causes

response to stress of difficult life experience / medical problem
disrupted hypothalamus (tells pituitary to tell adrenal cortex to produce more cortisol)
disrupted monoamine neurotransmitter systems (dopamine and serotonin)

depression brain differences

smaller hippocampus & PFC (like PTSD)
→ regions to help manage stress, damaged by excessive stress
activity in cortex areas linked to limbic system

major depression treatment

antidepressants → raise norepinephrine, serotonin, and dopamine levels
SSRIs are most common (reshape the synapse, effects take a few weeks)

deep brain stimulation, DBS can relieve intensive episodes resistant to other treatment forms

bipolar disorder symptoms

manic-depressive illness

high / manic episodes → boundless energy, racing thoughts, insomnia, substance abuse, harmful behaviors
low / depressive episodes → feelings of sadness or hopelessness, worry, suicidal thoughts

hypomanic → highly productive manic episodes, clue to more intense developing mania

BPD diagnosis / causes

no clear cause, set of symptoms is only way to test

family history of psych disorders contribute, some genetic changes (still unclear)

BPD treatment

anti-epilepsy drugs, lithium, or atypical antipsychotics → manic periods
antidepressants or cognitive behavioral therapy → depressed periods

most patients do not respond to treatment

schizophrenia symptoms

positive symptoms → hallucinations, delusions, confused thinking
negative symptoms → lack of motivation, inability to experience pleasure

typically appears between 15-25 (corresponding to development of PFC)

schizophrenia treatment

no cure, many symptoms do not respond to treatment

medications and behavioral therapy
antipsychotic drugs → damp the dopamine response (positive symptoms), cause tremors / movement side effects as seen in Parkinson’s
*first = chlorpromazine
newer drugs → suppress serotonergic activity (negative symptoms)

schizophrenia genes

mutations on genes that affect nerve cell growth, development, learning, and memory → possible targets for medications

schizophrenia and ciggarettes

nicotine relaxes rigid nerve cell shape and function in areas of brain affected → may be possible future treatment