exam 1 Flashcards
explains behavior from a biological and chemical point of view
psychobiologists seek to discover the relationships between behavior an the underlying physiological mechanisms
psychobiology
the stereotaxic instrument is utilized for proper placement of an electrode or cannula
an animal is anesthetized and then placed on the stereotaxic instrument- an electrode or cannula is permanently implanted into the brain
stimulation technique for studying the brain
a wire is connected to the electrode- weak electrical currents are passed through the wire
electrical stimulation
a cannula is placed in the brain, cannula may be metal (guide cannula) with thinner plastic tubing inserted into guide cannula or a hypodermic needle- chemical administered through the cannula
chemical stimulation
micro electrode recording from a single cell, EEG, electroencephalogram, gross electrical recording from a large brain area
electrical recording techniques
a stereotaxic instrument is deployed and part of the brain is removed, damaged, destroyed, or inactivated, then the behavior of the subject is carefully assessed
lesion method
sucking out tissue
aspiration lesions
burning the tissue
radio-frequency lesions
leucotome is stereotaxically positioned in the brain, then the blade swings out to make a cut (frontal lobotomy)
knife cuts
cooling a target area or injecting an anesthetic into the area
reversible lesions
animal is sacrificed at the end of the experiment
- brain is removed, placed in formalin, embedded in paraffin
- brain is then slice, stained, and examined
histological examinations
contrast x-ray technique that reveals blood vessels in the brain
before x ray is taken a radio-opaque dye is injected into the blood vessels that enter the brain
angiogram
individual images are obtained by passing x-rays through the head
a narrow x-ray beam is emitted by a source on one side of the head and a detector measures the number of x-ray photons that emerge on the other side
similar to conventional x-ray but many different sections through the brain are obtained
computerized axial tomography (cat scan)
similar to cat scan, but the signal arises from the decay of a radioisotope that has been injected into the patients circulation
a distinct advantage of this is the radioisotope (radioactive fluorodeoxyglucose) can be linked to glucose, the principal metabolic fuel of the brain
STUDYS FUNCTION
positron emission tomography (pet) scan
advantage is taken of the fact that the nuclei of atoms in the brain respond to magnetic field differentially, depending on their local atomic environment
by exposing the head to magnetic fields of different strengths, the computer assisted 3D image of the brain is made
magnetic resonance imaging (MRI)
combines structure and function
utilizes high powered, rapidly oscillating magnetic fields and powerful computation to measure the cerebral blood flow in the brain and obtain a measure of neural activity in the brain
produces images of the increase in oxygen flow in the brain to active areas of the brain
fMRI (functional magnetic resonance imaging)
this is a pattern recorded by electrodes from a specific part of the brain in response to a stimulus such as sight, sound, or touch
record how quickly and completely the nerve signals reach the brain and can indicate problems along nerve pathways that are too subtle to show up during a neurological examination or be noticed by the patient
evoked response potential (ERP)
receiving end, specialized for excitation
dendrites
controls metabolism of the cell
cell body (soma)
delivers impulses, specialized for conduction
Axon
area between cell body and axon of a neuron
axon hillock
a swelling at the end of an axon
terminal button
fatty insulation around many axons, aids in conduction, its found on neurons inside and outside of the CNS, nerve cells with this conduct faster than nerve cells without, its interrupted at regular intervals by the nodes of Ranvier
myelin sheath
inside of the CNS: astrocytes and oligodendrocytes
-provide nourishment for neurons
-provide support for neurons
-protect and insulate axons
-lay down the myelin sheath
satellite cells
outside of the CNS, in the peripheral nervous system
-protect and insulate neurons
- lay down myelin sheath
-involved in regeneration of damaged nerve fibers
schwann cells
this is found in sensory nerves sub serving somethesis (pain, touch, temperature, pressure) and kinesthesis (limb position)
axon is connected via a little neck to the cell body
unipolar neuron
found in the eye
connected directly to the cell body
bipolar neuron
this type is found in motor nerves
consists of a single long axon and a number of dendrites
motor neuron (multipolar neuron)
this is located predominantly in the spinal cord and brain and is the most numerous of all types of neurons in the nervous system
found in between other neurons
interneurons (multipolar neuron)
has a short, multibranching dendrites and a long axon, a structure that makes it ideally suited for transmitting information over long distances within CNS
projection neuron
axons of this area noticeably short and both its axons and dendrites show profuse branching (this enables it to establish multiple relations with other neurons)
typically receives information from a large number of sensory neurons or other interneurons and delivers information to a large number of motor neurons or other interneurons
local circuit neuron
towards head
rostral
towars tail
caudal
above a structure
superior
below a structure
inferior
towards midline
medial
away from midline
lateral
toward midline
proximal
away from midline
distal
front
anterior
back
posterior
base of brain, front
ventralback,
top of brain, back
dorsal
sensory
afferent
motor
efferent
bundles of neurons located outside of CNS
nerve
bundle of neurons located inside of CNS
tract
collection of nerve cell bodies located outside of CNS
ganglion
collection of nerve cells located inside of CNS
nucleus
12 pairs of these located inside the somatic nervous system which is located inside the peripheral nervous system
cranial nerves
- olfactory
- ent./exit from CNS- cerebrum
- no autonomic functions
- sensory: smell
-not a real nerve
cranial nerve I
- optic
- ent./exit from CNS- thalamus
- no autonomic function
- sensory: vision
- not a real nerve
cranial nerve II
- oculomotor
- exit from CNS- midbrain
- autonomic function: constricts pupils
- motor: eye movement, down and in
cranial nerve III
- trochlear
- exit from CNS- midbrain
- no autonomic function
- motor: eye movement up and out
cranial nerve IV
- trigeminal
- ent.&exit from CNS- midbrain, pons, medulla
- no autonomic function’
- sensory: from face & head
- motor: chewing
cranial nerve V
- abducens
- exit: pons and medulla
- no autonomic function
- motor: eye movement laterally
cranial nerve VI
- facial
- exit and ent.: medulla
- crying, accommodation, salivation
- sensory: taste (anterior 2/3 of tongue)
- motor: face movement
cranial nerve VII