Module 2: Biological and Neurological Basis Flashcards
What are the theoretical approaches in explaining the etiology of psychological disorders?
- One-dimensional
- Multi-dimensional
One-Dimensional etiology
looking for a single cause
Multi-Dimensional etiology
looking for a systemic cause
Genes
long molecules of DNA at various locations on chromosomes, within cell nucleus; carriers of the information we inherit from
our parents
Chromosomes
the chain-like structures within a
cell nucleus that contain the genes
How many chromosomes does a human have?
23 pairs of chromosomes (a total of 46 chromosomes)
+ 22 pairs of autosomes
+ 1 pair of sex chromosomes
What is the biological sex of someone who has XX chromosomes?
Female
What is the biological sex of someone who has XY chromosomes?
Male
Phenotypes
observable characteristics
Genotypes
unique genetic makeup
Polymorphisms
naturally occurring variations of
genes
Polygenic
influenced by multiple genes or by multiple polymorphisms of genes with any one gene having only very small effects
Endophenotypes
genetic mechanisms that ultimately contribute to the underlying problems causing the symptoms and difficulties experienced by people with psychological disorders
Basic Genetic Epidemiology
statistical analysis of family, twin, and adoption studies; if the disorder can be inherited and how much is attributable to genetics
Advanced Genetic Epidemiology
studies the factors that influence the disorder
Gene Finding
what gene influences the behavior
Molecular Genetics
biological analysis of individual DNA samples; biological processes genes affect to produce symptoms of the disorder
Family Studies
examine behavioral pattern or emotional trait in the context of the family
Proband
+ family member with the trait singled out for study
+ The first person in the family to be identified as possibly having genetic disorder and who may receive genetic counseling or testing
Adoption Studies
identify adoptees who have a particular behavioral pattern or psychological disorder and attempt to locate first-degree relatives who were raised in different family settings
Twin Studies
usually conducted to identical twins because they share genetic makeup
What kind of alleles/genes did the people who reported more severe stressful life events have?
Those people who reported more severe stressful life events and had at least one short allele of the 5-HTT gene were at greater risk of developing depression (Caspi et al., 2003) (serotonin-transporter gene)
Epigenetics
factors other than inherited DNA sequence, such as new learning or stress, that alter the phenotypic expression of genes
Neuroscience
study of the nervous system, especially the brain to understand behavior, emotions, and cognitive processes
Result of high dopamine
Schizophrenia
Result of low dopamine
Parkinson’s
Result of low acetylcholine
Alzheimer’s (Dementia)
Result of high norepinephrine
Mania
Result of low epinephrine
Depression
Result of high GABA
Relaxation
Result of low GABA
Anxiety, OCD
Result of high serotonin
mania
Result of low serotonin
depression, anxiety, eating disorders
Result of high epinephrine
stress, sleep disorders
Result of low epinephrine
fatigue
Result of high glutamate
psychosis, neuron death
Result of low glutamate
Huntington’s disease
Result of low endorphin
eating disorders
Synapse
a tiny fluid-filled space between the axon endings of one neuron and the dendrites or cell body of another neuron
Agonist
drug that effectively increase the activity of neurotransmitters (Excitatory)
Antagonist
decrease or block neurotransmitter (Inhibitory)
Inverse Agonists
produces effects opposite to those produced by the neurotransmitters
Reuptake
neurotransmitter is released, quickly broken down and brought back to the synaptic cleft
Hormones
chemical messengers secreted by endocrine glands in the body
Neurotransmitter
chemical messengers of the body
Types of Neurotransmitters
- Glutamate (E) (memory)
- GABA (I) (calming)
- Serotonin (I) (mood)
- Dopamine (pleasure)
- Epinephrine (fight-or-flight)
- Norepinephrine (concentration)
- Endorphins (euphoria)
- Acetylcholine (learning)
Glutamate (E)
most abundant in the brain and plays a key role in thinking, learning, and memory
GABA (I)
most common inhibitory neurotransmitter in the brain and regulates mood, irritability, sleep, seizures
Serotonin (I)
regulates mood, sleep patterns, sexuality, appetite, and pain
Dopamine
body reward system, pleasures, achieving heightened arousal and learning
Epinephrine
responsible for fight-or-flight repsonse
Norepinephrine
alertness, arousal, decision-making, attention, and focus
Endorphins
natural pain reliever, reduces pain
Acetylcholine
regulates heart rate, blood pressure and gut motility, role in muscle contraction, memory, motivation, sexual desire, sleep, and learning
Brain Stem
lower and more ancient part of the brain; essential for autonomic functioning such as breathing, heart rate, etc.
Parts of the Brain Stem
- Hindbrain
- Cerebellum
- Midbrain
- Thalamus and Hypothalamus
Hindbrain
contains the medulla, pons, and cerebellum; regulates many autonomic activities such as breathing, heartbeat, and digestion
Cerebellum
controls motor coordination abnormalities associated with autism
Midbrain
coordinates movements with sensory input and contains parts of reticular activating system (contributes to sleep, arousal, and tension)
Thalamus and Hypothalamus
involves in regulating behavior, emotions, and hormones
Limbic System
+ Located around the edge of the center of the brain
+ Regulate emotional experiences and expressions and, to some extent, our ability to learn and to control impulses
+ Related to Parkinson’s Disease
+ Attention, emotion, “fight or flight”
What are the parts of the limbic system?
- Hippocampus
- Cingulate Gyrus
- Septum
- Amygdala
Amygdala
emotions
Hippocampus
shrinks when a person has depression
Basal Ganglia
base of the forebrain, includes caudate nucleus
What will happen if the basal ganglia gets damaged?
Damage involved can change posture or cause twitching or shaking
Cerebral Cortex
provides us with our distinctly human qualities, allowing us to look to the future and plan, to reason, and to create
Left Hemisphere
responsible for verbal and other cognitive processes
Right Hemisphere
perceiving the world around us and creating images
Lobes
area responsible for higher cognitive functions
HPA Axis
hypothalamus, pituitary gland, adrenal cortex
Somatic Nervous System
controls the muscles
Autonomic Nervous System
regulate cardiovascular system and endocrine system
What are the kinds of the autonomic nervous system?
- Sympathetic
- Parasympathetic
Endocrine System
glands produce hormones that is released to the blood streams
What are the parts of the endocrine system?
- Pituitary
- Thyroid
- Parathryoid
- Adrenal
- Pineal
- Pancreas
- Testes
- Ovaries
Pituitary
master gland
Thyroid
controls metabolism and growth (thryoxine)
Parathyroid
controls the levels of calcium
Adrenal
controls metabolism, blood pressure, sex development, stress (epinephrine)
Pineal
releases melatonin
Pancreas
creates insulin
Testes
makes sperm and release testosterone
Ovaries
releases estrogen, progesterone, and testosterone
How does the hypothalamus-pituitary-adrenal axis function?
- Messages in the form of corticotropin-releasing hormone (CRH) travel from the hypothalamus to pituitary gland
- Pituitary Gland releases adrenocorticotropic hormone (ACTH), which stimulates the cortical part of the adrenal gland (located at the top of the kidney) to produce epinephrine (adrenaline) and cortisol (stress hormone), which is released into the general circulation
- Cortisol gives negative feedback to the hypothalamus and pituitary to decrease their release of CRH and ACTH, which in turn reduces the release of adrenaline and cortisol
Temperament
refers to a child’s reactivity and
characteristic ways of self-regulation
What are the five dimensions of temperament that can be identified?
As early as 2-3 months of age, approx. five dimensions of temperaments can be identified:
(1) fearfulness, (2) irritability/frustration, (3) positive affect, (4) activity level, and (5) attentional persistence/effortful
control
Permissive Hypothesis
when serotonin (norepinephrine) levels are low, other neurotransmitters are permitted to range more widely, become dysregulated, and contribute to mood irregularities
Corpus Callosum
communication between right and left hemisphere
Frontal Lobe
Learning, abstracting, reasoning, inhibiting
Hypothalamus
Regulation of metabolism, temperature, and emotions
Temporal Lobe
Discrimination of sounds, verbal, and speech behavior
Reticular Formation
Arousal reactions, information screening
Medulla
Breathing, blood pressure, other vital functions
Cerebellum
Fine motor coordination, posture, and balance
Occipital Lobe
Visual discrimination and some aspects of visual memory
Thalamus
Major relay station for messages from parts of the body, important sensations of pain
Parietal Lobe
Somesthetic motor discriminations and functions
Sensory Strip
Integration of sensory information from various parts of the body
Motor Strip
Regulation of voluntary movement
