Midterm Flashcards
How does cocaine effect the synapse?
Blocks Dopamine Reuptake Transporters by clogging receptors
What causes the addictive euphoric/pleasurable effects of cocaine?
Dopamine which has accumulated in the synapse due to inhibited reuptake overstimulates the mesocorticolimbic dopamine system
What is Cocaine?
A CNS Stimulant which increases neural and behavioral activity and boost energy temporarily
The effects of cocaine resemble those exerted by which nervous system?
Sympathetic Nervous System
What are some Physical and Psychological effects of Cocaine?
Increased loco motor activity, heart rate, temperature, and blood glucose
Pupil dilation
Euphoria, racing thoughts, reduced appetite
What effect do drugs have on the mesocroticolimbic dopamine system?
Supraphysiological dopamine - dopamine release much larger than that caused by normal rewarding stimuli
This hijacks the reward system causing the brain to over prioritize behavior and stimuli associated with the drug
What are the effects of dopamine released to the Nucleus Accumbens (NAc)?
Feelings of subjective pleasure
What are the effects of dopamine released to the Hippocampus?
Learned association between rewarding feeling and stimuli
What are the effects of dopamine released to the PFC?
Cognitive control necessary to seek/avoid the stimulus
What are the pathways of the Mesocorticolimbic Reward System?
Neurons in the Ventral Tegmental Area (VTA) containing Dopamine project their axons to the Hippocampus, Nucleus Accumbens (NAc), and Prefrontal Cortex (PFC)
What is Intracranial Self-Stimulation (ICSS)
A rat is fitted with an electrode in certain parts of the brain which can be stimulated by a lever, when placed in certain areas the rat will press the lever endlessly, ignoring other rewarding stimuli, until it becomes exhausted or needs to be forcefully removed
What is Reward and why does it exist?
Stimuli that are in some way desirable and can affect behavior
Designed to motivate animals to engage in life-sustaining endeavors such as reproduction, eating, and maintaining social relationships
The DSM-5 characterizes Substance Abuse Disorder as maladaptive pattern of use that has led to subjective distress for a year as well as at least 2 of what six symptoms?
- Substance use results in failure to fulfill obligations
- Spend a great deal of time trying to obtain the drug
- Legal problems associated with drug
- Craving
- Tolerance
- Withdrawal
How do drugs effect Homeostasis?
- Brain normally exists in a state of drug free homeostasis
- Taking drugs lead to an imbalance
- Compensatory adaptations attempt to restore homeostasis
What is addiction?
Uncontrolled drug use that persists in spite of negative consequences
What is Tolerance?
Increase in dose required to obtain desired effects of drug
What is Withdrawal?
Physical and psychological behaviors that are displayed by an addict after drug use ends
What is Substance Use?
Occasional, moderate use of a substance which does not interfere with everyday life
What is Substance Abuse?
When use of a substance significantly interferes with everyday life functions
What is Substance Dependence?
Physiological and psychological dependence on a substance - resulting in tolerance and withdrawal
What is a Psychoactive Drug?
Substances which act to alter mood, thought, cognition or behavior
What is a CNS depressant?
A psychoactive drug which suppresses mental functions and at low doses results in calming effects but at high doses results in intoxication
Alcohol, Anxiolytic, Opiates
What is a CNS Stimulant?
A drug which stimulates arousal and gives a boost in energy and clarity
Amphetamine, Cocaine, Caffeine, Nicotine
What is a Hallucinogen?
A drug which disturbs ones sense of reality
MDMA, LSD, Marijuana
What compensatory actions lead to Cocaine tolerance?
- Some Dopamine receptors on the postsynaptic terminal are removed
- Dopamine release is reduced from the presynaptic terminal
What is Anhedonia?
Inability to feel pleasure
What does the Dopamine Hypothesis of Schizophrenia suggest?
That the symptoms of schizophrenia rise due to excessive amounts of dopamine
Hyperactivity and Hypoactivity of which connections effecting dopamine release are involved in Schizophrenia?
Hyperactivity of the mesolimbic connections (VTA-NAc and VTA-Hippo) result in over stimulation of D2 receptors resulting in Positive symptoms
Hypoactivity of the Mesocortical connections (VTA-PFC) result in under stimulation of D1 receptors resulting in Negative and Cognitive symptoms
Enlargement of what brain structures suggests that there is a change in cellular makeup, density, or organization of the Schizophrenic brain which is being replaced by CSF?
Enlarged Ventricles
The Schizophrenic brain tends to have reduced brain volume in which areas and what symptoms are a result of this?
Frontal and Temporal Lobe - Cognitive and Language Deficits
Basal Ganglia - Reduced Emotional Control and Motoric Changes
Hippocampus - Learning and Memory Deficits
What is psychosis?
A Group of psychological disorders in which patients experience a loss of contact with reality