Chapter 18: Anxiety Disorders Flashcards
agoraphobia
Fear of public places.
alcohol
Ethyl alcohol is an organic compound that is a product of fermentation and belongs to the class of sedative–hypnotics.
anticipatory anxiety
Feeling of extreme worry over the possibility that a certain unpleasant event will occur in a particular, often public, situation.
anticonvulsants
Drugs, such as benzodiazepines, that prevent or control seizures. They are used to treat epilepsy.
anxiolytics
Drugs that alleviate feelings of anxiety in humans and that reduce anxiety-related behaviors in animals.
behavioral desensitization
Technique used to treat phobias by introducing the fear-inducing stimulus in increments, allowing the patient to maintain a relaxed feeling in its presence.
buspirone (Buspar)
Drug that stimulates 5-HT1A receptors. Symptoms include increased appetite, reduced anxiety, reduced alcohol cravings, and a lower body temperature. It is prescribed as an antianxiety medication.
CNS depressants
Large category of drugs that inhibit nerve cell firing within the central nervous system. They include sedative–hypnotics and are used to induce sleep and to treat symptoms of anxiety; include barbiturates, benzodiazepines, alcohol (all reduce neuron excitability)
compulsions
Repetitive tasks that an individual feels obligated to complete in an effort to quell the anxiety caused by obsessive thoughts.
general anxiety disorder
An anxiety disorder characterized by excessive worrying that does not have a specific cause.
hypnotics
Drugs, such as benzodiazepines, that help a patient to fall asleep and stay asleep.
long-acting drug
Drug that has low lipid solubility, taking more than an hour to reach the brain. Slow metabolism or presence of active metabolites allows for prolonged effects that persist for long periods.
muscle relaxants
Drugs, such as benzodiazepines, that reduce muscle tension in a patient.
obsessions
Worrying thoughts or ideas that an individual cannot easily ignore
obsessive–compulsive disorder (OCD)
Psychiatric anxiety disorder characterized by persistent thoughts of contamination, violence, sex, or religion that the individual cannot easily ignore, and that cause the individual anxiety, guilt, or shame, etc. and may be accompanied by compulsive repetitive behaviors.
panic attack
Feeling of extreme fear that was not preceded by a threatening stimulus.
panic disorder
Disease involving repeated attacks of extreme fear, occurring either without warning or in an environment similar to where previous panic attacks occurred.
phobias
Fears of specific objects or situations that are recognized as irrational.
posttraumatic stress disorder (PTSD)
Emotional disorder that develops in response to a traumatic event, leaving the individual feeling a sense of fear, helplessness, and terror. Symptoms include sleep disturbances, avoidance of stimuli associated with the trauma, intrusive thoughts reliving the event, and a numbing of general emotional responses. An increase in suicidal thoughts has also been observed.
sedative–hypnotics
Class of drugs that depresses nervous system activity. They are used to produce relaxation, reduce anxiety, and induce sleep.
short/intermediate-acting drugs
Drugs that are moderately lipid-soluble, reaching the brain within 20 to 40 minutes. The drugs lose effectiveness over time due to liver metabolism.
ultrashort-acting
Drugs that are highly lipid-soluble, reaching the brain within seconds when administered intravenously. They lose effectiveness quickly, as they rapidly redistribute to inactive drug depots in fat, bone, and muscle.
amygdaloid complex
structure deep within the temporal lobes; major component of several emotional processing circuits
components of emotional processing circuits
amygdala, limbic cortex, hypothalamus, hippocampus
what do the emotional circuits do?
evaluate environmental stimuli, contextual cues and cognitions that have emotional relevance and initiate appropriate responses via the amygdala
where does the amygdala receive information from
sensory thalamus, sensory and association cortices, hippocampal formation
what does the central nucleus of the amygdala do?
orchestrates the components of fear: ANS activation, enhanced reflexes, increased vigilance, activation of the hypothalamic-pituitary-adrenal (HPA) axis, and others
why does the central nucleus of the amygdala have such widespread effects?
because it has connections with multiple brain areas; lateral hypothalamus- activates sympathetic nervous system; periaqueductal gray- causes freezing; locus coeruleus- initiates arousal and vigilance
what is the central nucleus of the amygdala essential for?
the fear response
what does the bed nucleus of the stria terminalis (BNST) do?
called the extended amygdala; responsible for the behavioral responses in anxiety; projects to the same areas as the amygdala but acts differently
response by central nucleus of the amygdala
is rapid
how does the response of the BNST differ from the central nucleus of the amygdala?
initiates components of the emotional response when the stimuli are less precise predictors of a potentially dangerous situation. It produces a state of sustained preparedness for an unclear danger and a prolonged period of anticipation that something unpleasant might occur; persists long after the initial stimulus is ended
alterations of BNST
chronic and unpredictable stress increases dendritic length and branching as well as volume of BNST;
what modulates BNST?
sex hormones–may explain gender differences
what does the amygdala help form?
emotional memories aka conditioned fear response; making an association between an environmental stimulus and an aversive stimulus; emotional memories are established quickly and are long lasting
connection between the amygdala and hippocampus?
contributes to the enhancement of memory consolidation through its connections with hippocampus
role of hippocampus in anxiety
reciprocal connections with the amygdala modulate emotional responses on the basis of context
role of PFC
fear extinction–learning that a cue that once predicted danger no longer does
corticotropin-releasing-factor
small neuropeptide that controls the neuroendocrine (HPA axis), autonomic, and behavioral responses to stress.
what activates the HPA axis?
the release of CRF from the hypothalamus in response to stress
what does CRF cause?
inducing the anterior pituitary to release the stress hormone adrenocorticotropic hormone (ACTH) into the blood, which in turn increases the release of glucocorticoids such as cortisol from the adrenal cortex
what does elevated levels of cortisol lead to?
a negative feedback loop by binding to receptors in the hippocampus, hypothalamus and pituitary, which inhibits HPA axis function and brings cortisol levels back to normal
intraventricular administration of CRF
stimulates the sympathetic nervous system and causes increases in plasma adrenaline and increased heart rate and blood pressure
effects of CRF
wide-ranging on feeding, GI activity, and energy balance that are consistent with preparation for dealing with environmental stressors
direct neuronal effects of CRF
strong excitatory effects;
where are a lot of CRF nerve endings found?
the amygdala
locus coeruleus
major cluster of noradrenergic cell bodies in the dorsal pons that send axons rostrally to several brain areas to increase vigilance and attention to physiologically relevant stimuli
reciprocal connection between the locus coeruleus and the amygdala
provide a mechanism for generating arousal, orienting and responding to fear evoking stimuli
effects of NE agonists and antagonists
alpha2-autoreceptor antagonist (yohimbine) increases NE release and leads to fear response; alpha2 agonist reduces NE leads to antianxiety effects
NE and anxiety
is the neurotransmitter released at the target visceral organs, including heart, during sympathetic activation. the catecholamine adrenaline released from the adrenal medulla produces widespread effects that prepare the individual to respond to danger
what does NE play a role in?
formation of emotional memories
is it possible to stop formation of traumatic memories?
yes—blocking beta-adrenergic receptors right after a severe trauma; this may also disrupt already consolidated traumatic memories and associated physiological responses
beta blockers and emotional memories
they do not seem to impair declarative memory of the association of the conditioned and unconditioned stimuli but diminishes the emotional effects
how to benzodiazepines work?
NE cells in the NE locus coeruleus are excited by CRF synaptic input and are inhibited by y-aminobutryic acid (GABA) and serotonin (5-HT), as well as by stimulation of alpha2-adrenergic somatodendritic autoreceptors. benzodiazepines enhance the inhibitory function of GABA, reduced LC firing may be responsible for some of the anxiolytic effects
GABA
inhibitory amino acid neurotransmitter; modulates anxiety
GABAa receptor complex
comprises a chloride Cl- channel that when opened following GABA binding allows Cl- to enter the cell, causing hyperpolarization; several sedative hypnotics enhance function of GABA causing sedation and reduced anxiety