Psychopharmacology, Neurophysiology & PTSD/Trauma Presented by Craig Strickland, Ph.D. strickkat@verizon.net.

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Psychopharmacology, Neurophysiology & PTSD/Trauma

Presented by Craig Strickland, Ph.D.

https://sites.google.com/site/bioedcon

strickkat@verizon.net

Learning Objectives

• List the 3 general categories of symptoms associated with PTSD

• Describe the role of structures in the central nervous system (CNS) associated with these symptoms

• Summarize the advantages and disadvantages of the various psychotropic medication classes used to treat PTSD

Overview of the Symptoms

of Post-Traumatic Stress

Disorder

Major Symptom categories of PTSD

1. The event is persistently re-experienced

2. Persistent avoidance of stimuli and numbing of general responsiveness

3. Negative alterations in cognitions associated with the trauma

4. Persistent symptoms of increased arousal

Differential Diagnosis

• Adjustment Disorder• Acute Distress Disorder• Personality Disorders• Mood Disorders• Other Anxiety Disorders• Psychotic Disorders• Substance Induced

Disorders• Other (e.g. medical?)

Differential diagnosis is based not

just on the mere presence or

absence of certain symptoms

Trauma as seen on a continuum

Acute Stress Disorder

PTSD Chronic PTSD

Complex Trauma

Symptom Duration & Severity

Overview of the Human Nervous System

Hierarchy of CNS Structures

Inferior Parietal (Logical Processing)

Cingulate Cortex(attention & affect)

Entorhinal Cortex Hippocampus

Amygdala (fear/anxiety)

Septal NucleiLateral

Hypothalamus

Reticular Formation

PeripheralAutonomics

Prefrontal Cortex(motivation)

The Hippocampus and PTSD

The Hippocampus

Hippocampus

Normal Functions of the Hippocampus

• The hippocampus is a very complex structure

• Is part of the Limbic System

• Considered “transitional” tissue

• Normal functions include (but may not be limited to)

– Memory consolidation: works together with newer cortical brain areas

• Integration of “emotional tone” with “higher” cognitive functions

• Cortex provides semantic influence to the more episodic (factual) “hippocampal” memories

– Behavioral inhibition

– Inhibitory influence on brainstem activity

The Hippocampus & Trauma

• Decrease volume (size) of the hippocampus

– This is a robust finding

• Vietnam vets: 8 to 26% reduction depending on the study

• 7% reduction in women with history of childhood sexual abuse

• 16% reduction in hippocampal volume in women with BPD (often associated with a history of abuse)

– Seen in other psychiatric disorders such as schizophrenia

– Has been shown to occur in animal models involving experimental stressors

Chicken or the Egg?

The Chicken or the Egg? (Gilbertson, et.al. 2002)

Gilbertson, et.al. 2002

Chicken or Egg? (cont.)

• Apfel, et. al. (2011)

– Gilbertson study did not contain true longitudinal data

– This of course would be nearly impossible to do in this type research

– Apfel study looked at hippocampal volume in 244 male Gulf War Veterans

• Study included those with current PTSD and those where the symptoms of PTSD were remitted

Chicken or Egg? (cont.)

• In addition to measuring symptoms of PTSD (using the Clinician Administered PTSD Scale (CAPS) assessment tool:

– Measured presence or absence of depression

– Measured lifetime drinking history

– History of other (non-combat related) stressors

• Used structural MRI techniques to measure hippocampal volume

Chicken or Egg? (cont.)

• Ended up with four groups of subjects

– Subjects with no traumatic exposure

– Subjects with exposure but no PTSD

– Subjects with a previous diagnosis of PTSD but have recovered

– Subjects with chronic PTSD (lifetime and current)

• The first two groups had identical hippocampal volume and were combined into one group for the further analysis

Chicken or Egg? (cont.)

• Results

– Subjects with current/lifetime PTSD

• 6.5% smaller hippocampi than those who had recovered from PTSD

– Subjects with current/lifetime PTSD:

smaller hippocampi by 5.1% than those who had never developed PTSD

– Note: there was no difference in hippocampal size between those who never had PTSD and those who had recovered from PTSD

• Interpretations?

Chicken or Egg? (cont.)

• The results raise the possibility that hippocampal volume is state-dependent and might vary over time e.g. the hippocampus may itself recover from the effects of PTSD; support for this interpretation?

– Duration & severity of PTSD symptoms are negatively correlated with hippocampal volume

– Hippocampal volume can increase as a result of long-term Paxil treatment

– Hippocampal volume might change as a result of exercise, other medications and abstinence from alcohol

• E.G. Neurogenesis

Symptoms Associated with Hippocampal Damage? (Re-experiencing)

• Dissociation and/or intrusive thoughts

• Illusions and/or hallucinations

• Behavioral disinhibition: causes the definition of incoming stimuli towards fight/flight responses

• Along with amygdaloid activation, hippocampal damage may prevent proper evaluation & categorization of experiences/stimuli

– May lead to reacting to new or neutral stimuli as threatening

– This would lead to either aggressive behavior or possibly to withdrawal

The Limbic System and PTSD:

The Amygdala

Limbic System: The Amygdala

Connections Revisited

Inferior Parietal (Logical Processing)

Cingulate Cortex(attention & affect)

Entorhinal Cortex Hippocampus

Amygdala (fear/anxiety)

Septal NucleiLateral

Hypothalamus

Reticular Formation

PeripheralAutonomics

Prefrontal Cortex(motivation)

Normal Functions of the Amygdala

• Normal amygdala functioning

– Evaluates the emotional significance of incoming stimuli (emotional meaning)

– Amygdala activated by feared stimuli (conversely, destroying the amygdala through surgery eliminates fear responses)

– Amygdala mediates fear related behaviors

• Does so through the hippocampus, hypothalamus and certain cortical areas (prefrontal cortex)

• E.g. has an “upstream” and “downstream” effect

Symptoms associated with Amygdaloid hyperactivity (hyperarousal)

• Neutral stimuli are seen as fearful

– Through connections with other limbic structures, enhanced autonomic and neurohormonal responses

• Increased sympathetic nervous system activity

• Hypervigilance

• Exaggerated startle response

• Irritability or outbursts of anger

– Increased Hypothalamic/Pituitary Adrenal axis activity (known as HPA)

The HPA

• Affected by amygdala

activation or lack of

hippocampal influence

• Increased activity in

persons with anxiety as

well as persons with

depression…hmmm…

Cortical Areas and PTSD

Frontal Cortex Dysfunction

Inferior Parietal (Logical Processing)

Cingulate Cortex(attention & affect)

Entorhinal Cortex Hippocampus

Amygdala (fear/anxiety)

Septal NucleiLateral

Hypothalamus

Reticular Formation

PeripheralAutonomics

Prefrontal Cortex(motivation)

Prefrontal Cortex: Activity Decrease

Persistent Avoidance/Numbing

• Symptoms include (but not limited to):

– Cannot recall important trauma details (memory)

– Markedly diminished interest/participation in significant activities

– Felling of detachment/estrangement from others

– Restricted range of affect (unable to express love, etc.)

– Sense of foreshortened future

WHAT OTHER DISORDER DO THESE SYMPTOMS REMIND YOU OF?

(Are you ready for some “Craigism”?)

MRI of Depression

Dissociative Phenomena (cont.)

• “Physiologically, they may respond as if they are being traumatized again, but this may be dissociated from semantic knowledge” (van der Kolk, 1997)

Dissociative Phenomena (van der Kolk)

• Failure of left-hemisphere functioning at the time of the trauma (i.e. during extreme arousal)

– Decreased activation of Broca’s area (Broca’s area is involved in labeling emotions)

• Cannot communicate what is going on, cannot label the internal state

• Thus, during extreme arousal/intense emotions, the individual cannot “understand” what is going on

– Left-hemisphere: also involved in sequencing events and categorizing experiences. Dysfunction leads to:

• Trauma being seen as timeless

• Trauma being seen as “ego-alien”

Psychopharmacology and PTSD

Psychopharmacology and PTSD

• Issues regarding the use of medications with this disorder

– There are no “anti-PTSD” medications (although there are two FDA approved medications for PTSD)

– Co-occurring substance abuse disorders

– Other co-occurring psychiatric disorders (both Axis I and Axis II diagnoses)

– Co-occurring medical disorders

– Lack of medication development compared with other disorders

What are the Neurotransmitters?

• Monoamines

– Dopamine (DA)

– Norepinephrine/epinephrine (NE/E)

– Serotonin (5-HT)

• Gamma amino butyric acid (GABA) and other amino acids (Glutamate, glycine, etc.)

• Acetylcholine (ACh)

• Hormones

• Neuromodulators

Variety of Medications Used

• Anti-depressants

– Monoamine Oxidase Inhibitors (MAOIs)

– Selective Serotonergic Re-Uptake Inhibitors (SSRI)s: Prozac, Paxil, Zoloft, Celexa, Luvox and Lexapro)

– Novel Anti-depressants: Desyrel, Serzone

– Tricyclic anti-depressants: Elavil, Norpramin

• Benzodiazepines

• Anti-convulsant mood stabilizers

• Anti-adrenergic: Inderal, Clonidine & Guanfacine

• Opioid antagonists: Revex, Naltrexone

• Anti-psychotic medications

SSRIs: Increase Serotonin Activity

• Advantages of the SSRIs (Zoloft, Paxil, etc.)– Can help treat both anxiety and depression– Can reduce impulsivity/enhance sobriety associated

with substance abuse– Can be effective in all three symptom clusters

associated with PTSD• Behaviors associated with serotonin in the brain

include impulsivity, rage, suicidal behavior, depression, panic, obsessional thinking and behaviors associated with substance abuse• Difficult to OD on SSRIs

– Disadvantages: do not (nor do any other medications) seem to affect dissociation

Novel Anti-Depressants

• Trazodone (Desyrel)

– Advantages:

• Increases 5-HT similar to SSRIs

• Can reverse insomnia caused by

SSRI agents and may help

reduce traumatic nightmares

• Not addictive

Anti-depressants and Lifestyle

Anti-Adrenergic: Decrease NE levels

• Inderal, Clonidine and Guanfacine all decrease norepinephrine levels

– Advantages:

• Reduces hyperarousal and perhaps symptoms of re-experiencing

• May help reduce D/A dependence particularly opiate dependence

• Side-effects are transient and mild (unless one has pre-existing cardiovascular issues)

• Not addictive

– Disadvantages:

• Half-life is short (tolerance)

• Can make co-occurring depression worse

Recent data on NE antagonist

• Prazosin: reduces NE activity

– FDA approved to reduce BP and reduce enlarged prostate

– Used to reduce traumatic nightmares

– Not a sedating sleeping pill (does not induce sleep)

– Blocking NE centrally may normalize and increase REM sleep

– Does not induce tolerance although the beneficial effects wear off once & symptoms return once the drug is stopped

Reducing NE at the time of the traumatic event

• Reducing NE shortly after the traumatic event may have two neurological effects:

– May have an anti-anxiety effect (established by reducing NE peripherally)

– May help reduce memory consolidation by blocking NE centrally (NE activity is part of memories being consolidated ); this may lessen the more long-term reactions associated with stimuli resembling the traumatic event (article in Neuropsychiatry)

Benzodiazepines (BZDs)• Includes meds. such as Valium, Librium, Halcion,

Xanax, Ativan

– Advantages:

• Very effective at reducing anxiety, insomnia and irritability

• Reduces these symptoms very quickly

– Disadvantages• BZDs have addictive potential• Do not reduce core PTSD symptoms (e.g. re-

experiencing, avoidant nor numbing symptoms)• Behavioral disinhibition (similar to alcohol)• Memory interference• Consumers may confuse the sedative properties

with the anti-anxiety properties

Anti-Convulsants (Mood Stabilizers)

• Includes Tegretol, Depakote and Gabapentin

– Advantages:

• May reduce proposed “kindling” of limbic structures

• Tegretol: may reduce re-experiencing and arousal symptoms

• Depakote may reduce avoidant/numbing and arousal symptoms

– Disadvantages:

• Need to be careful of potential OD (toxicity)

• Sedation

– Neurontin, Lamictal and Topamax

Opiate Antagonists (Naltrexone, Revex)

• The brain: releases increased amounts of endogenous opiates (endorphins, etc.) in response to stimuli which resemble the original traumatic event

– This may account for the symptoms of emotional numbing and stress-induced analgesia• Advantages:–May reduce numbing and stress-induced

analgesia–May interfere with drug (alcohol/opiate)

seeking behavior– Reduce self-mutilation behaviors (BPD)

• Disadvantages:

–May make hyperarousal/anxiety worse

Eye Movement Desensitization &

Reprocessing (EMDR)

Normal Sleep Processes: REM Sleep

• Re: memory formation, information flows from the hippocampus to cortical areas during non-REM sleep (basis for reinforcement of old memories)

• During REM sleep the flow is reversed– Information flows from cortical areas to the

hippocampus and– Hippocampal outflow is blocked

• During REM sleep there is a preferential activation of limbic structures (including amygdala)

• Thus, REM sleep provides a method of forming new associative links (provides/enhances semantic processes and integrates this with any appropriate emotional tone)

REM Sleep and EMDR

• PTSD interrupts the normal REM process:

– Intrusive replay of hippocampal episodic memories of the traumatic events occurs

– The associated primitive emotional reactions (via the amygdaloid) occur as well

– However, the cortical input which provides meaning or sense to the events is missing

• Eye Movement Desensitization & Reprocessing (EMDR): may be a treatment which allows for the proper integration of cortical input with episodic memory and emotional tone

Sleep Disorders

Classification of Sleep Disorders: Secondary to other conditions

• Psychiatric Disorders• Drug or alcohol use• Psychiatric medications• Medical disorders (e.g.

respiratory; cardiac)• Medications for medical disorders• Pain syndromes

(taken from M. Gitlin, 1996: The Psychotherapist’s Guide to Psychopharmacology)

Medications used to regulate sleep

• Ambien/Ambien CR • Chloral hydrate• Lunesta• Sonata• Hydroxyzine

(Vistaril; Atarax)• Rozerem

• Benzodiazepines (BZDs)– Restoril– Ativan– Other BZDs

• Sedating anti-depressants

• Anti-histamines• Sedating neuroleptics

How do sleep aids work?

BZDs BZD-like meds.

Anti-histamines

Melatonin agonists

Unknown

Restoril Ambien Benadryl Rozerem Choral Hydrate

Ativan Sonata Vistaril Melatonin supplements

Other BZDs

Lunesta Atarax

Desyrel (trazodone)

Thank you for Coming!!!

WHEW!

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