EXAM 1 REVIEW Flashcards
What is the genetic evidence for schizophrenia?
If someone in your family has schizophrenia, your chances of having it are higher. Identical twins have about a 50% chance of both having schizophrenia if one is affected.
What physical changes are observed in the brains of people with schizophrenia?
Larger fluid-filled spaces (ventricles) and less gray matter, indicating differences in brain structure.
What does the dopamine hypothesis suggest about schizophrenia?
Schizophrenia is linked to too much dopamine activity in some brain areas, contributing to hallucinations and delusions.
This theory focuses on the positive symptoms of schizophrenia but we have to remember that schizophrenia is a 2 parter- there are also negative symptoms that would need to be treated associated in the mesocortical pathway.
Dopamine-blocking drugs help reduce symptoms, supporting this hypothesis.
What is the key point of the NDMA (Glutamate) Theory?
This theory states that N-Methyl-D-Aspertate (NMDA) receptor HYPOfunction (low levels) causes schizophrenia.
Glutamate is the main excitatory neurotransmitter, meaning it helps brain cells “turn on” and communicate effectively.
It works through NMDA receptors, which help in learning, memory, and thinking.
What is the neuropil hypothesis?
The density of neurons is decreased in schizophrenia. The number of neurons is the same as they are in a healthy human, but in schizophrenia these neurons are tightly packed together. This means they cannot branch out and make connections as they usually would.
What prenatal complications are associated with a higher risk of schizophrenia?
Lack of oxygen at birth, infections during pregnancy, and malnutrition.
Studies indicate that maternal flu during pregnancy increases risk.
What is the significance of the Finnish adoption study in understanding schizophrenia?
It showed that children born to mothers with schizophrenia but raised in healthy families had a lower risk of developing the disorder, highlighting the role of environment.
This underscores the gene-environment interaction in schizophrenia.
What are the positive symptoms of schizophrenia?
Hallucinations, delusions, disorganized thinking, agitation, and unusual behavior.
These symptoms arise from too much dopamine in the mesolimbic pathway.
What are the negative symptoms of schizophrenia?
Lack of motivation (avolition), apathy, social withdrawal, and flat affect.
These symptoms are linked to too little dopamine in the mesocortical pathway.
What is the role of the prefrontal cortex in schizophrenia?
Responsible for executive functions like decision-making, and impulse control.
Aggression and agitation is also related to the prefrontal cortex.
Dysfunction in this area can contribute to cognitive symptoms.
True or False: Antipsychotic medications are equally effective for positive and negative symptoms of schizophrenia.
False
Antipsychotics are more effective for positive symptoms and may worsen negative symptoms.
What is the impact of urban living on the risk of developing schizophrenia?
Higher likelihood of developing schizophrenia, potentially due to stress, pollution, and social isolation.
Urban environments may exacerbate underlying genetic vulnerabilities.
What is the significance of auditory hallucinations in schizophrenia?
They are activated in the auditory cortex of the temporal lobe, with increased activity in gray matter during episodes.
White matter tract abnormalities in the arcuate fasciculus are also associated with these hallucinations.
What are the major dopamine pathways involved in schizophrenia?
Mesolimbic, mesocortical, nigrostriatal, and tuberoinfundibular pathways.
What is the GABA interneuron hypothesis?
There is reduced GABA function, particularly in a type of GABA neuron called parvalbumin (PV) interneurons.
GABA is the main inhibitory neurotransmitter, meaning it helps brain cells “turn off” or slow down activity. Weak GABA inhibition leads to too much chaotic brain activity, disrupting thoughts and perception.
What is the connection between dopamine and prolactin in antipsychotic treatment?
Dopamine inhibits prolactin release; blocking dopamine increases prolactin levels, leading to side effects.
Increased prolactin can cause breast enlargement and menstrual irregularities.
What cognitive symptoms are associated with schizophrenia?
Memory problems, poor decision-making, and disorganized thinking.
These symptoms arise from dysfunction in the prefrontal cortex and neurotransmitter imbalances.
True or False: First-generation antipsychotics are less likely to raise prolactin levels compared to second-generation antipsychotics.
False
First-generation antipsychotics are more likely to increase prolactin levels.
What impact does synaptic pruning have in schizophrenia?
Pruning may occur too aggressively, leading to fewer connections in important brain areas like the frontal cortex.
This can affect planning, problem-solving, and emotional regulation.
What is the primary role of the amygdala?
Processing emotions, especially fear and aggression
It plays a role in emotional memory and the fight-or-flight response.
Where is the amygdala located?
Deep within the medial temporal lobe, adjacent to the hippocampus.
What are the main functions of the hypothalamus?
Regulates autonomic functions including body temperature, hunger, thirst, and circadian rhythms.
Plays a major role in the endocrine system by controlling hormone release through the pituitary gland.
Where is the hypothalamus located?
Below the thalamus and above the brainstem.
What is the primary responsibility of the cerebellum?
Coordinating movement and balance.
Where is the cerebellum located?
At the back of the brain, underneath the occipital lobe.
What is the function of the innate immune system?
Provides the first line of defense against pathogens
Includes physical barriers, phagocytic cells, and inflammatory responses.
How does the adaptive immune system function?
Generates long-term immunity through specialized responses
Includes B cells and T cells that recognize specific antigens.
What is the function of cytokines and how is it associated with shizophrenia?
Involved with neuroplasticity.
People with schizophrenia often show increased pro-inflammatory cytokines which lead to increased inflammation in the brain causing diseases such as schizophrenia.
Cytokines regulate brain inflammation, and imbalances are linked to schizophrenia.
✅ Pro-inflammatory cytokines are elevated, increasing dopamine activity and excessive synaptic pruning.
What is the function of the complement system and how is it associated with schizophrenia?
Overactive Complement System (C4 Gene in Schizophrenia).
The C4 gene plays a role in the immune system and helps remove weak or unused synapses.
In schizophrenia, overactive C4 leads to excessive pruning, especially in the prefrontal cortex, which can cause cognitive problems and hallucinations.
What does the HPT axis regulate?
Metabolism and overall brain function through thyroid hormones.
What are the effects of hypothyroidism?
Linked to negative symptoms of schizophrenia such as depression, cognitive impairment, and mood disturbances.
What is the function of the HPA axis?
Regulates the body’s response to stress by releasing cortisol.
What is a consequence of overactivation of the HPA axis?
Chronic Stress, Depression, and Anxiety.
Hippocampus (memory center):
Impaired memory.
Hippocampal shrinkage (brain volume decreases).
Decreased neurogenesis (fewer new neurons are made).
Amygdala (fear & emotion center):
Overactivated by glucocorticoids (stress hormones).
Leads to increased anxiety & heightened fear responses.
What are the potential effects of hyperthyroidism?
Associated with anxiety, irritability, and restlessness.
What are the 3 neurotransmitter theories linked to schizophrenia?
- Dopamine Hypothesis
- Serotonin Theory
- Glutamate (NMDA) Theory
How do you make a NMDA receptor work?
The NMDA receptor is a subtype of glutamate receptor requires a coreceptor (glycine) to work effectively. When these receptors are underactive they are associated with schizophrenia.
What is epigenetics?
DNA is modified by environmental effects. Those genetic changes that are modified by those environment end up being transmitted to offspring.
What is the nigrostriatal pathway associated with?
The nigrostriatal pathway is associated with Parkinson’s has to do with motor movement.
Especially voluntary versus involuntary motor movement. So under normal conditions, there’s no problems there. But in conditions like Parkinson’s disease, there is too little dopamine in the nigrostriatal pathway, we get involuntary motor movements.
What is the tuberoinfundibular pathway associated with?
Regulates prolactin, a hormone involved in breast development and lactation.
(boob tube)
When dopamine is blocked here, prolactin levels rise. This is important for schizophrenia medications that block dopamine (antipsychotic meds) because this can lead to side effects such as breast development in men, etc.
How did Brodman distinguish the different brain areas?
By the cellular structure.
What are important notes related to the hippocampus?
Memory and Learning.
Hippocampus is also one of the few areas in the brain where neurogenesis occurs in adults. (New neurons help with both memory and learning).
How is GABA, glutamate, and dopamine all interconnected in schizophrenia?
Glutamate NMDA hypofunction leads to loss of GABA inhibition.
This overstimulates dopamine neurons in the mesolimbic pathway, leading to excess dopamine release in the nucleus accumbens (causing hallucinations/delusions).
Meanwhile, prefrontal dopamine levels decrease, leading to cognitive and negative symptoms.
