Stress & The HPA Axis
What is the primary glucocorticoid hormone released by the adrenal cortex during a stress response?
Cortisol
Which brain region acts as the central hub for processing fear and anxiety, playing a critical role in panic attacks?
Amygdala
Almost all addictive drugs share the common property of increasing dopamine release in which specific mesolimbic structure?
Nucleus Accumbens
Alcohol exerts its sedating and anxiolytic effects primarily by acting as an agonist or positive modulator on which receptor?
GABA (GABA-A receptor)
What term refers to the intrusive, unwanted, and anxiety-inducing thoughts that precede compulsive rituals in OCD?
Obsession
Which hormone is released by the hypothalamus to officially initiate the activation of the HPA axis?
CRH (Corticotropin-Releasing Hormone)
What chemical compound can be administered in a laboratory setting to artificially trigger a panic attack in susceptible individuals?
Lactic Acid (Lactate) / or Carbon Dioxide (CO_2) inhalation
What term describes the decrease in sensitivity to a drug after repeated exposure, requiring the user to increase the dose for the same effect?
Tolerance (Cellular desensitization)
THC, the active ingredient in cannabis, exerts its effects by binding to which naturally occurring receptor system in the brain?
Cannabinoid Receptors (CB_1 and CB_2) / Endocannabinoid System
OCD shares a strong genetic and neurological link with which motor disorder, characterized by facial and vocal tics?
Tourette's Syndrome
Chronic elevation of glucocorticoids causes structural changes in hippocampal neurons. Specifically, which cellular alteration occurs in the dendrites of CA1 and CA3 pyramidal cells during prolonged stress?
Dendritic atrophy (or retraction/loss of dendritic branches/loss of dendritic spines).
Benzodiazepines, used for the acute treatment of anxiety, exert their therapeutic effects by targeting which neurotransmitter receptor?
GABA-A Receptor
Reinstatement of drug-seeking behavior (relapse) involves a major projection from the prefrontal cortex using which neurotransmitter?
Glutamate
Endogenous opioids (endorphins) inhibit pain by activating receptors in which specific midbrain gray matter region?
Periaqueductal Gray (PAG)
Patients with OCD typically exhibit hyperactivation in which specific basal ganglia structure involved in motor loops?
Caudate Nucleus
Early-life stress (e.g., maternal separation) permanently reduces the expression of glucocorticoid receptors in which brain area?
Hippocampus
In individuals with PTSD, which prefrontal region fails to properly inhibit the amygdala, impairing the extinction of fear memories?
Ventromedial Prefrontal Cortex (vmPFC)
What term describes the opposite of tolerance, where the brain becomes more sensitive to a specific effect of a drug over time?
Sensitization (Behavioral or motor sensitization)
What is the primary mechanism of action for stimulants like cocaine and amphetamine regarding neurotransmitter clearance?
Blocking the reuptake of Dopamine (and Norepinephrin) via transporters
What non-invasive surgical alternative uses a magnetic coil to stimulate the dorsolateral prefrontal cortex in treatment-resistant OCD?
TMS (Transcranial Magnetic Stimulation)
Glucocorticoids released during chronic stress suppress the immune system by interfering with messages sent between white blood cells. Specifically, glucocorticoids inhibit the production of which class of immune signaling proteins, which are normally responsible for commanding white blood cells to proliferate and attack infections?
Cytokines (Interleukins)
Which brainstem structure, rich in noradrenergic neurons, is heavily involved in the acute, sympathetic symptoms of opiate withdrawal?
Locus Coeruleus
While the mesolimbic pathway is crucial for reward, another brain area that is absolutely necessary for the physical development of addiction. Animals with lesions in this specific somatosensory cortical area fail to develop a preference for places associated with drug use and find it significantly easier to quit smoking. Which cortical area is this?
Insula (Insular cortex)
While acute alcohol intake enhances GABA-A receptor function, chronic alcohol abuse leads to a dangerous compensatory neuroadaptation. Which specific ionotropic glutamate receptor system is upregulated (increased) to counter alcohol's inhibitory effects, potentially causing fatal seizures during withdrawal?
NMDA receptors
Neuroimaging studies of patients with OCD consistently show metabolic hyperactivity in a specific cortical area that projects directly to the caudate nucleus. Which prefrontal cortical region is this, heavily involved in evaluating the emotional value of stimuli?
Orbitofrontal Cortex (OFC)