Neuroanatomy, neurophysiology, and behavior Flashcards
components of the neuron
cell body (soma)
stem/axon: transmit signals away from body to connect with other neurons/cells
dendrites- collect incoming signals
2 separate divisions of the nervous system
CNS and PNS
PNS is comprised of..
somatic nervous system: info from CNS to skeletal muscles. Control voluntary movement
autonomic nervous system: regulate internal body functions, homeostasis. info from CNS to smooth muscle, cardiac, glands. Control involuntary movement. Divided into 2 parts
2 parts of the autonomic nervous system
Sympathetic: excitatory, prep for stress (fight flight), stimulates or increases activity of organs
Parasympathetic: maintains or restores energy, inhibits or decreases activity of organs
white matter and grey matter
White matter is the myelinated axons of neurons.
Gray matter is nerve cell bodies and dendrites; it is the working area of the brain and contains the synapses, the area of neuronal connection.
sulci and fissures and gyri
increase surface area of the brain for communication
Sulci: Small shallow grooves
Fissures: Deeper groves extending into the brain
Gyri: raised tissue areas
Distinct anatomical areas of the brain
cerebrum and brainstem
what connects to two sides of the brain and what is it
corpus callosum
an area of sensorimotor info exchange
Each hemisphere is divided into four
Frontal occipital parietal temporal
Frontal lobe size and development
Largest and most developed
Frontal lobe functions
Motor function: voluntary activity of specific muscles
Pre-motor area controls coordinated movement of multiple muscles
Association cortex: multimodal sensory input to trigger memory and lead to decision-making
Seat of executive function: memory reasoning, planning, prioritizing, sequencing, insight, flexibility, judgment, impulse control, behavioral queuing, intelligence, abstraction
Language (Broca) expressive speech
Personality variables: the most focal area of personality development
Problems in the frontal lobe can lead to
Personality changes, emotional, and intellectual change changes
Temporal lobe functions
Language (Warneke‘s area) : receptive speech or language comprehension
Primary auditory area
Emotion
Memory
Integration of vision with sensory information
Problems with temporal lobe
Visual or auditory hallucinations, aphasia, amnesia
Occipital lobe functions
Primary visual cortex
Integration area: integrates vision with other sensory information
Problems in the occipital lobe
Visual field defects
Blindness
Visual hallucinations
Parietal lobe functions
Primary sensory area
Taste
Reading and writing
Problems in the parietal lobe
Sensory perceptual disturbances and agnosia
Cerebrum parts
Cerebral cortex, limbic system, thalmus, hypothalamus, basal ganglia
Cerebral cortex function
Controls wide array of behaviors
Controls, contralateral, or opposite, side of the body
Sensory info from thalamus processed and integrated in the cortex
Responsible for what makes us human colon speech, cognition, judgment, perception, motor function
Limbic system function
Regulate and modulate emotions and memory
Limbic system parts
Hypothalamus, thalmus, hippocampus, amygdala
Hypothalamus function
Regulates, appetite, hunger and thirst sensation, water, balance, circadian, rhythms, body temperature, libido, hormonal regulation
Thalamus function
Sensory relay, except smell
Modulate flow of sensory info to prevent overwhelming the cortex
Regulate emotions, memory, related affective behaviors
Hippocampus function
Regulates memory
Converts short-term memory into long-term
amygdala function
Mediates mood, fear, emotion, aggression
Connecting sensory smell information with emotion
basal ganglia AKA
Corpus striatum
Basal ganglia function
Modulates and stabilizes somatic motor activity (CNS to skeletal muscles)
Movement initiation, complex motor functions
Functions in learning an automatic actions, like walking or driving a car
Part of extrapyramidal, motor system or nerve tract
Involuntary motor actions like muscle tone, posture, coordination of muscle movement, reflexes
What can many psychotropic medication’s do to the basal ganglia?
He can affect the extra pyramidal motor, nerve track, causing involuntary movement side effects
parts of the basal ganglia
caudate and putamen
Problems in the basal ganglia lead to
Bradykinesia, hyperkinesias, dystonia
Brainstem is made up of cells that produce
neurotransmitters
Brainstem parts
Midbrain
Pons
Medulla
Cerebellum
Reticular Formation System
Midbrain
Home to the ventral tegmental area and the substantia nigra (DOPEAMINE SYNTHESIS)
Pons
home to the locus ceruleus (NE synthesis)
Medulla
With pons, contains autonomic control centers that regulate internal body functions
Cerebellum
Equilibrium
gross movement control center (balance/posture)
Each hemisphere has ipsolateral control (same side of the body
Problems with cerebellum lead to
ataxia (uncoordinated and inaccurate movements)
Test for cerebellar deficiency
romberg
Reticular formation system
primitive brain
input from cortex to integrate postsensory pathways
innervates thalmus, hypothalmus, cortex
Reticular formation system regulation functions
involuntary movement
reflex
muscle tone
vital sign control
blood pressure
respiratory rate
critical to consciousness and ability to mentally focus (alert/attention)
2 classes of cells in the nervous system
glia
neurons
Glia cells
form the myelin sheath around axons and provide protection and support
2 phases of an action potential
depolarization
repolarization
depolarization
initial phase of an action potential (excitatory response) when sodium and calcium ions flow into the cell
repolarization
restoration phase (inhibitory response) when potassium leaves the cell or chloride enters the cell
Synaptic problems in structure or chemistry lead to
interruption of normal flow which contribute to sx seen in psychiatric disorders
Categories of neurotransmitters
monoamines
amino acids
cholinergics
neuropeptides
Criteria for classification for neurotransmitters
NT present in the nerve terminal
Stimulate neuron causes release of NT enough to cause an action at postsynaptic membrane
effect of exogenous transmitter on postsyn must be similar to those cause by stim of presyn
mechanism of inactivation or metabolism of the NT must exist in the synapse
exogenous drugs should alter the dose response curve of the NT similar to natural occuring
monoamines
AKA biogenic amines
Ex: Dopamine, norepinephrine, epinephrine, serotonin
Catecholamines
dopamine, norepi, epi
dopamine produced in the
substantia nigra and the ventral termental area
dopamine precursor
tyrosine
dopamine removed from synaptic cleft by
monoamine oxidase (MAO) enzymatic action
4 dopaminergic pathways
mesocortical
mesolimbic
nigrostriatal
tuberoinfundibular
NE produced in the
locus ceruleus of the pons
NE precursor
tyrosine
NE removed from synaptic cleft by
and returns to storage by active reuptake process
NE is the NT implicated in
mood, anxiety, and concentration disorders
Epinephrine produced by
adrenal gland
epinephrine system AKA
adrenergic system
5HT is not a catecholamine it is an
indole
5ht produced in the
raphe nuclei of the brainstem
5ht precursor
tryptophan
5ht removed from synaptic cleft and returned to storage via
active reuptake process
5ht NT implicated in
mood and anxiety disorders
Amino acids examples
glutamate
aspartate
GABA
glycine
Glutamate
universal excitatory NT
glutamate as major NT involved in process of
kindling: so seizure disorders and possibly Bipolar
imbalance implicated in mood and schizophrenia
aspartate
another excitatory NT that works with glutamate
GABA
universal inhibitory NT
GABA is the site of action of
benzos, alcohol, barbituates, and other CNS depressants
glycine
another inhibitory NT that works with GABA
cholinergics
acetylcholine
acetylcholine location synthesized
basal nucleus of meynert
acetylcholine precursors
acetylcoenzyme A and choline
neuropeptides types
nonopioid type, opioid type
neuropeptides non opioid types
substance P, somatostatin
neuropeptides opioid types
endorphines, enkephalins, dynorphins
neuropeptides modulate
pain
decreased amount thought to cause substance abuse
how does recovery and degradation of NTs work
after postsyn: destroyed by enzyme or transported back to presyn for reuse
enzymatic destruction in either cytosol or synapse
enzymes that destroy are MAO in the cytosol or COMT in synapse or intracellularly
reuptake pumps remove NT from syn for reload into presyn and recycling
Imbalance ACH decrease leads to
Alzheimers, impaired memory
Imbalance ACH increase leads to
parkinsonian symptoms
Imbalance dopamine increase leads to
schizophrenia, psychosis
Imbalance dopamine decrease leads to
substance abuse
anhedonia
parkinsons disease
Imbalance NE decrease leads to
depression
Imbalance NE increase leads to
anxiety
Imbalance 5ht decrease leads to
depression, OCD, anxiety, schizophrenia
Imbalance GABA decrease leads to
anxiety disorders
Imbalance glutamate increase leads to
bipolar, psychosis from ischemic neurotoxicity or excessive pruning
Imbalance glutamate decrease leads to
memory and learning difficulty
negative sx of schizophrenia
Imbalance opioid neuropeptides decrease leads to
substance abuse
2 dopamine receptors
D1 and D2
General function of dopamine
thinking
decision-making
reward seeking behavior
fine muscle action
integrated cognition
Sx of deficit of dopamine (Mild)
Poor impulse control
Poor Spatiality
Lack of abstract thought
Sx of deficit of dopamine (Severe)
Parkinsons disease
Endocrine alterations
movement disorders
Sx of excess of dopamine (Mild)
Improved creativity
improved ability for abstract thinking
improved executive functioning
Improved Spatiality
Sx of excess of dopamine (Severe)
Disorganized thinking
Loose association
Tics
Stereotypic behavior
2 NE receptors
@1 @2
General function of NE
Alterness
focused attention
orientation
primes “fight or flight”
learning
memory
Sx of deficit of Norepinephrine
Dullness
low energy
depressive affect
Sx of excess of Norepinephrine
Anxiety
hyperalterness
increased startle
Paranoia
Decreased appetite
Serotonin receptors
5ht1a
5ht1d
5ht2
5ht2a
5ht3
5ht4
general function of serotinin
regulation of sleep
pain perception
mood states
temperature
regulation of aggression
libido
precursor of melatonin
Sx of deficit of serotonin
irritability
hostility
depression
sleep dysregulation
loss of appetite
loss of libido
Sx of excess of serotonin
sedation
increased aggression
hallucination (rare)
ACH receptors
nicotinic
muscarinic
general function of Ach
attention
memory
thirst
mood regulation
REM sleep
Sexual behavior
muscle tone
Sx of deficit of Ach
lack of inhibition
decreased memory
euphoria
antisocial action
speech decrease
dry mouth, blurred vision, constipation
Sx of excess of Ach
over-inhibition
anxiety
depression
somatic complaints
self-consciousness
drooling
extrapyramidal movements
GABA receptors
GABAa
GABAb
general function of GABA
reduces arousal
reduces aggression
reduces anxiety
reduces excitation
Sx of deficit of GABA
irritability
hostility
tension and worry
anxiety
seizure activity
Sx of excess of GABA
reduced cellular excitability
sedation
impaired memory
general function of Glutamate
memory
sustained autonomic functions
Glutamate receptors
AMPA
MNDA
Sx of deficit of glutamate
poor memory
low energy
distractable
Sx of excess of Glutamate
kindling
seizures
anxiety or panic
Peptide: opioid type receptors
mu
kappa
epsilon
delta
sigma
general function of Peptide: opioid type
modulate emotions
reward center function
consolidation of memory
modulate reactions to stress
Sx of deficit of peptide opioid type
hypersensitivity to pain and stress
decreased pleasure sensation
dysphoria
Sx of excess of peptide opioid type
insensitivity to pain
catatonic like movement disturbance
auditory hallucinations
decreased memory
3 techniques to observe the brain
structural imaging
functional imaging
combined structural and functional
structural imaging of the brain
CT
inexpensive and shows size/shape
but lack sensitivity (white vs gray matter, cant view close to bone, bad with atrophy identification, no sagittal/coronal views
MRI
2D, close to skull ok, separate white/gray/superior to CT
but expensive, many contraindications, claustrophobia
functional imaging of the brain
bases results on blood flow, may use radioactive pharma to cross BBB, mainly used for research
EEG: least expensive, focus on electrical functioning of the CNS
MEG: similar but different electrical activities
SPECT: cerebral blood flow, expensive
PET: most expensive, needs a support team
combined structural and functional imaging of the brain
fMRI
3fEMRI
fluorine magnetic spectroscopy
dopamine receptor binding
