Neurobiology and Psychiatric Pharmacotherapy and Behavioral Theories

Advanced Imaging and Physical Factors in Mental Health

• PET and SPECT Scans:     - PET Scan: Previously mentioned diagnostic tool for brain activity.     - SPECT (Single Photon Emission Computed Tomography):         - Referred to in the transcript as "SPEC, s e c t."         - Operates similarly to a PET scan but is specifically useful for visualizing the circulation of cerebrospinal fluid (CSF).         - Clinical Applications: Identifying anatomical or physical issues such as tumors or Chiari malformation (where CSF is prevented from exiting through the vertebral column into the spinal cord).         - Focus: Generally treated as a tool for medical or physical issues rather than purely mental health issues.

• Physical vs. Mental Health Overlap:     - Pressure buildup in the head from stalled fluid displacement can cause symptoms that overlap with mental health disorders.     - It is critical to rule out physical causes before making a mental health diagnosis.

• External Factors Influencing Mental Health:     - Drugs, infection, hormones, and trauma.     - Diathesis-Stress Model: Referenced in the transcript as the "Thymeophysis stress model."         - This model explains that individuals with a genetic disposition reach a threshold for mental illness much faster and easier than those without the disposition when facing stressors.

Neurobiology and Mechanism of Brain Communication

• Chemical Alterations: Mental health is influenced by alterations in brain chemicals, including:     - Monoamine transmitters.     - Amino acid transmitters.     - Neuropeptides.     - Acetylcholine.

• Cellular Composition:     - Neurons: The primary elements in the brain that respond to stimuli.     - Neurotransmitters: Chemicals that facilitate messages traveling from neuron to neuron.     - Significance: The amount of a neurotransmitter (too much or too little) directly influences brain function. It was not until the $1950\text{s}$ that medical science recognized medications could alter these chemicals to decrease psychological symptoms.

• The Synaptic Process:     - Vesicles: Small sacs in the presynaptic neuron that contain thousands of neurotransmitter molecules.     - Action Potential: An electrical signal that excites the presynaptic neuron, causing vesicles to fuse with the membrane.     - Synaptic Cleft/Synapse: An extremely tiny gap between neurons where neurotransmitters are released.     - Receptors: Sites on the postsynaptic neuron that receive the chemical signal.     - Reuptake: The process where neurotransmitters flow back into the original neuron to be "digested," broken down, and recycled (described as a "used car lot").     - Enzyme Destruction: Enzymes (like $MAO$) can break down neurotransmitters within the synapse.

Communication Analogies: Phones and Football

• The Phone/Texting Analogy:     - Phone A: Sending/Presynaptic neuron.     - Type Message: The buildup of action potential energy.     - Hit Send: The release of neurotransmitters into the synapse.     - Data/World: The synaptic gap between phones.     - Phone B: Receiving/Postsynaptic neuron/Receptor site.     - Notification Alert: Successful reception by the receptor.     - Low Serotonin/Disease: Phone A doesn't send enough messages, or Phone B has a full inbox/voicemail (impaired reception).

• The Football Activity (Simulated Synapse):     - Imbalance Scenarios:         - Less than normal transmitters, normal receptors: Receptors sit empty, and signals are missed.         - Normal transmitters, fewer receptors: Transmitters are "floating" in the synapse without a home.         - Enzyme Reuptake (The Blocker): An individual acting as an enzyme ($MAO$) takes the football from the receiver and returns it to the sender to be recycled.         - Enzyme Destruction: The individual takes the football and destroys it rather than returning it.

Psychopharmacology and Medication Mechanisms

• Medication Actions on the Synapse:     - SSRIs, SNRIs, and TCAs: These medications block the reuptake of neurotransmitters. This keeps more serotonin or norepinephrine in the synapse for longer (the "delete button" on the phone is blocked).     - MAOIs (Monoamine Oxidase Inhibitors): They block the enzymes that break down neurotransmitters, allowing more to be recycled and utilized.     - Benzodiazepines (Benzos):         - Enhance specific receptors ($GABA$) to increase its effect.         - Described as a "football block" that causes the neurotransmitter to keep being recycled/available, leading to a calming effect.     - Antipsychotics: Work to block specific receptors (like dopamine) to prevent over-reception by the postsynaptic neuron.

• Agonists vs. Antagonists:     - Agonist: Mimics the effect of the neurotransmitter by binding to and stimulating the receptor (increases action).     - Antagonist: Blocks the neurotransmitter, decreasing or obstructing its action.

• Clinical Considerations:     - Medication Grids: Students must document classification, mechanism, uses (including off-label), interactions, side effects, and patient education.     - Adherence: Patients must not abruptly stop psychiatric medications. Consistency is vital, especially for SSRIs which require time to build up in the system.

Neurotransmitter Profile Summary

• Dopamine ($DA$):     - High (Hyper): Schizophrenia, Mania. Symptoms: Elevated emotions, fidgeting, tremors, flight of ideas, hallucinations, paranoia, hypersexual behavior.     - Low (Hypo): Parkinson’s disease, Depression. Symptoms: Low emotions, decreased coordination, muscle rigidity, fatigue, difficulty paying attention.

• Norepinephrine ($NE$):     - High (Hyper): Mania, Anxiety, Schizophrenia. Symptoms: Elevated mood, unable to focus, fight-or-flight activation (pupil dilation, increased heart/respiratory rate).     - Low (Hypo): Depression. Symptoms: Low energy, weight gain, decreased attention.

• Serotonin ($5\text{-}HT$):     - High (Hyper): Anxiety, Serotonin Syndrome. Symptoms: Insomnia, agitation, restlessness, shivering, diarrhea, muscle rigidity.     - Low (Hypo): Depression. Symptoms: Fatigue, oversleeping, low mood, decreased libido, altered pain perception (tolerance can increase or decrease).

• GABA (Gamma-Aminobutyric Acid):     - High (Hyper): Reduction in anxiety, sluggishness, sleepiness, muscle relaxation (effect of Benzos).     - Low (Hypo): Anxiety, Schizophrenia, Mania, Huntington’s Disease. Symptoms: Aggression, impulsivity, restlessness, irritability, muscle spasticity.

Psychological Theories and Therapies

• Psychoanalysis (Freud):     - Belief: Must understand history/past childhood experiences to deal with current emotions.     - Concepts: Conscious/Unconscious layers, Id, Ego, Super-Ego.     - Defense Mechanisms: Operate at an unconscious level to decrease anxiety (e.g., Denial).     - Transference: Patient projects feelings/ideologies onto the therapist.     - Countertransference: Therapist develops feelings toward the patient based on their own personal history.     - Other Theorists mentioned: Erickson, Piaget, Sullivan.

• Behavioral Theory:     - Belief: Behavior can be manipulated for desired outcomes; the "why" is less important than the "how."     - Pavlov: Involuntary responses via conditioning (e.g., child vomiting at the sight of a medicine bottle).     - Watson: Personality traits are learned through conditioning.     - Skinner: Voluntary behaviors are learned through reinforcement (e.g., rats performing tricks for treats).

• Therapy Types:     - Exposure Therapy: Used for PTSD and phobias. Requires specialized training to avoid retraumatization.         - Systematic Desensitization: Slow, gradual introduction to fears using coping mechanisms (e.g., dipping toes in water).         - Flooding: Rapid, direct exposure to the fear (e.g., throwing a child in a pool).     - Operant Conditioning: Positive reinforcement (e.g., using chocolate to reward behavior).     - Aversion Therapy: Pairing negative habits with unpleasant stimuli (e.g., bitter solution on fingernails for nail-biters).     - Biofeedback: Using equipment (watches, rings, monitors) to gain insight into physiological processes to control them.     - Thought Stopping: A behavioral technique to interrupt negative or repetitive thought patterns.

Questions & Discussion

• Question about GABA/Benzos: A student asked why someone would want "more" GABA.     - Response: Benzos make the postsynaptic (following) neuron less reactive overall, which calms the brain down.

• Administrative Discussion: Discussion regarding clinical preceptorship checklists.     - Students must have their checklists signed by April 5.     - Students should take a photo of the signed document because the university (specifically referenced as U of I) will ask for a copy before the preceptorship begins.

• Page References:     - Page $41$: Chart for neurotransmitter increases/decreases.     - Page $21$: Chart for general signaling effects.

• Instructor Personal Note: Mentioned having a minor concussion and whiplash from being rammed at $40\text{ mph}$ at a stoplight, which might affect the lecture delivery.