Summery of PSYC Chapter 1 1/27/2013 12:32:00 PM
- Early in time, people believe that they posse mind, soul, spirit.
- the Mind-Body question: what role does the mind play? Does it control
the nervous system? Is it a part of the nervous system? It is physical and
tangible, like the rest of the body, or it is a spirit that will always remain
- Dualism: belief in the dual nature of reality. Mind and body are separate;
the body is made of ordinary matter, but the mind is not.
- Monism: belief that everything in the universe consists of matter and
energy and that mind is a phenomenon produced by the workings of the
nervous system (mind is a byproduct of our nervous system)
- Our sense organ and our lab instruments are manifestation of the
physical world: matter and energy.
Blindsight: it is a phenomena that is seen after partial damage to the
mammalian visual system on one side of the brain
- definition: several phenomena involving the human brain provide insight
(洞察力)into the nature of consciousness. One of these phenomena, cause
by damage to a particular part of the brain is known as bindsight.---if
damaged, cannot perceive the world into conscious.
- the human brain contain 2 mechanism of vision: the case is that the
patient is blind, but he can still reaching things by using his the primitive
mammalian system: we can perceive the world around us.
Primitive visual system: involve in frogs and fish. Mainly fct is to
control eye movements and bringing our attention to sudden
movement that occur out of our visual system.
- visual information can control behavior without producing a conscious
sensation. The phenomena of blindsight tells that consciousness is not a
general property of all part of brain. Only the mammalian visual system in
the human brain has direct connections with the parts of the parts of the
brain responsible for consciousness.
- parts of the brain involved in verbal behavior is responsible for
consciousness. - the left hemisphere control speech. Cut the corpus callosum in epileptic
seizure will result in: patient can understand conversation, but he cannot
EX: The left brain process smell info. If we cut the corpus
callosum, and we take a rose to the right nose, the person will
not smell the odor since the 2 hemispheres are disconnected. If
we ask the patient to take the object corresponding to the odor
by using the left hand, it is ok. But patient fail to do so with right
hand because the right hemisphere do not distinguish odor.
- we become conscious only if the info enter the part of the brain
responsible for verbal communication (on the left hemisphere)
- due to the damage to the cortex of the parietal lobe
- the parietal lobe:
receive info from skin, muscle, joint, internal organ, part of inner
ear, and visual/auditory info
concern with body position and balance
put movement of body parts together regarding the demand of
the environment---perceive the world and act with body
The nature of behavioral neuroscience
- behavioral neuroscience was formerly known as physiological
The goal of research
- scientific explanation takes two forms: generalization and reduction. All
scientist deal with generalization
generalization: the classification of phenomena according to their
essential features so that general laws can be formulated---
tradition method of psychology
reduction: the description of phenomena in terms of more basic
physical processes---physiological events
- the task of the behavioral neuroscientist is to explain behavior by
studying the physiological processes that control it. They cannot use
reduction because same behavior can be induced by different
physiological processes. - physiological mechanism can tell us something about the psychological
processes; this relationship is true of complex such as language, memory
Biological root of behavioral neuroscience
- Hippocrate says that BRAIN is responsible for through and emotions, but
not the heart.
- Aristotle says that BRAIN serve to cool the passions of the heart.
- Galen is not agree with Aristotle for 2 reason: BRAIN is not close to
heart and it has other connections with other sensory nerves.
- Descartes (dualism) assume that
world is a mechanical entity, and set up by GOD.
Animal and human are machines that controlled by
Some movements are involuntary---reflexes. They are cause by
environmental energy reflect back to CNS, and CNS cause
A link exist btw mind and brain. Mind control the body
movements, and brain is the manager to make body move in
order to respond to mind.
Brain has hollow chambers filled with fluid
The body mind interaction in the PINEAL BODY (on top of the
brain stem). Mind decide an action, it will tilt pineal body which
will then pressurize the fluid-- pineal body cause fluid flow to
nerves- nerve cause muscle contraction
-Luigi Galvani: nerve and muscle still contacting even through detached
from the body.
- Johannes Muller:
understanding of the working of the body would be achieved
only by removing or isolating animals organs, testing their
responses to various chemicals, and otherwise altering the
environment to see how the organ responded.
All nerve carry electrical impulse, but different nerves will
perform different action
Experimental ablation: remove various parts of animals’ brains
and observe their behavior. See what they cannot do, we will
know the fct of the missing part of the brain.
- Brocas’ area: necessary for speech - primary motor cortex: stimulation f different portions of a specific region
of the brain caused contraction of specific muscle on the opposite side of
- Hekmholtz: measure the speed of nerve conduction, much slower than a
Natural Selection and Evolution
- Darwin formulated the principle of MATURAL SELECTION and
EVOLUTION, which revolutionized biology
all of an organism’s characteristics (structure, function,
coloration, behavior) have FUNCTIONAL significance
his theory give rise to FUNCTIONALISM, a belief that
characteristics of living organisms perform useful functions.---we
cannot say that any physiological mechanisms of living
organisms have a PURPOSE, but they have a FUNCTION
EX: Camouflage: the wing of a butterfly when folded look like the
bulk and a tree. When a bird approach it, it open the wing and
there are 2 eye spots on the wings which prevent the bird from
eating the butterfly.-----NATURAL SELECTION (this is responsible
for the development of the species).
If an individual’s characteristics permit it to reproduce more
successfully, some of the individual’s offspring will inherit the
favorable characteristics and will themselves produce more
offspring. And that characteristic will be more prevalent in that
Mutation: accidental changes in the chromosomes of sperm or
eggs that joint together and develop into new organism. Most of
the mutation are harmful, offspring dies. Only a small portion is
SLECTIVE ADVANTAGE to the organism. This could be resistance
to disease, ability to digest new kind of food, etc. This treat will
pass onto the next generations.
Effect of these physical alternation can be seen in organism
behavior, so the process of natural selection act on behavior
Evolution (develop gradually) and the Human Species
- the process of evolution is a gradual change in the structure and
physiology of plant and animals species as a result of natural selection - SYNSAPSIDS is the ancestor of today’s mammals
- the 1 PRIMATE were small and preyed on insects and small cold-blood
- Large species develop forward-facing eyes to facilitate locomotion and
the capture of prey.
- the only hominids besides human who have survived: chimpanzees,
gorillas, and orangutans.
Human and chimpanzee: 1% difference in DNA
Homo erectus- Homo neanderthalis- Homo Sapiens
Evolution of Large Brain
- characteristics of humans:
agile hands, color vision, mastery of fire, upright posture,
linguistic abilities (require large brain): enable them to combine
collective knowledge of all the member, pass info to next
generation, establish civilization--- help them to become the
the neural circuit of human brain can be modified with
Bigger body require bigger brains, the size of the brain does not
have to go up proportionally with that of the body
The brain size of nonhuman hominids increase very little with
size: a gorilla weights almost 3X as a chimpanzee, but their brain
size is only 29% more
brain also vary in number of neurons that control brain
development: large primate contain more neurons per gram than
rodent brain do.
In human, the brain is still growing after birth (weight: 350g 100
The fetal skulls are more similar than those of the adults
compare to chimpanzee.
Ethical issues in Research with animals
- research with animals= evaluation of the benefits the research has to
human - animal use in research is necessary in terms of human progression:
vaccine, treatments for disease, medications, etc.
- cannot replace animals with tissue culture or computer: no way to study
behavioral problems such as addictions in tissue cultures, nor can we
program a computer to stimulate the workings of an animal’s nervous
Careers in Neuroscience
- Behavioral Neuroscience: study all behavioral phenomena that can be
observed in nonhuman animals (some study human), using non invasive
physiological research methods. They want to understand the physiology
of behavior: the role of the nervous system when interact with the rest of
- the study are done as sensory processes: aggressive behavior, sexual
behavior, parental behavior, learning and memory.
- they also study animal models of disorders that afflict humans such as
anxiety, depression, obsession, compulsion, phobias, psychosomatic
illness, schizophrenia Summery of PSYC Chapter 2 1/27/2013 12:32:00 PM
- LOCAL interneuron form circuits with nearby neurons and analyze small
pieces of info. RELAY interneuron connect circuits of local interneurons in
one region of the brain with those in other region.
- the NS consist of 2 divisions: CNS (brain and SP they are encased by
skull ad the spinal column) and PNS (periphery nerves of most sensory
Cells of the Nervous System
- NEURON info processing and info transmitting
many shape and varies in terms of what job they perform
consist of: cell body (soma), dendrites; axons, terminal buttons.
o SOMA: contain the nucleus and provide life process of the
cell. The shape varies depending the type of neurons
o DENDRITES: neurons talk to each other, and the dendrites
are the recipients of these messages. The message are
transmitted across SYNAPSE (junction btw the cell
terminals). Communication is always unidirectional from
terminals to the next cell membrane.
o AXON: long tube, and covered by myelin sheath, carry info
form cell some to terminals.
Basic message is ACTION POTENTIAL which start at
the end of the axon next to the cell body and travel
to the terminals
Three types of axons:
1. Most common in CNS: multipolar axons:
somatic membrane gives rise to one axon but
many dendritic trees
2. Bipolar axons: communicate with CNS. One
axon and one dendritic tree, sue to sensory
3. Unipolar axons: has one branch leaving the
cell soma and give rise to branch, one serve as
axon and one is dendritic tree. It detect the
sensory info particular: touch, temperature
change, any events that affect the skin, joints,
muscle and internal organs.
Nerves are bundles of many thousand of individual
fibers, all wrapped in a tough protective membrane. o Terminal Buttons: release neurotransmitters when AP
travelling down the axons. neurotransmitters could be
excitatory or inhibitory (may activate or inhibit the
receiving the cell)
- INTERNAL STRUCTURE of NEURON
the membrane: consist of 2 layer of lipid molecules
different proteins with different fcts are imbedded inside
o proteins can detect outside environment, control access of
other things into the cell, transporter, exchange nutrients
o proteins serve as enzyme (catalyst) that can control
the nucleus: responsible for production of ribosomes which is
involved in proteins synthesis. The chromosome contain genetic
info, once activated, they produce mRNA. When mRNA leave the
nucleus and attach to ribosome, protein synthesis occur.
o 1.5% of our DNA encode for gene
o other are junk DNA, but they have special fcts in cell.
When they are transcribed into RNA, they become non-
coding RNA, and will be cut away in the process. They form
the spliceosome. Non-coding RNA regulate gene expression
Cytoplasm: jelly like, and suspended organelles are found in
o Form a double membrane, inside the cell, it has cristae
o Extraction of energy and breakdown of nutrients are taking
place on the cristae.
o Cell provide mitochondria nutrients, and mitochondria
provide cell with ATP
ER: serve as a storage reservoir and as a channel for
transporting chemicals through the cytoplasm
o Rough ER: contain ribosome, the rough ER will leave the
cell or become part of cell membrane when protein in
ribosome go out of the cell
o Smooth ER: provide channels for separation of cells
involved in various cellular processes. Lipid molecules are
produced here Golgi Apparatus: special form of SMOOTH ER, complex molecules
that are made by simple molecules are assembled here. It
produce LYSOSOME which breakdown non-need substances in
Cytoskeleton: insoluble strands of proteins, matrix, backbone of
the neuron. It made up of three proteins strands. The most thick
o Microtubule: perform a movement called anterograde
axoplasmic transport: a way that needed items from the
cytoplasm can be reached to the entire length of axon.
o Kinesin walk down the length of microtubule and bring
things to axon. this process need ATP
o Dynesin do the reverse of Kinesinfrom terminals to some.
This is called retrograde axoplasmic transport.
o Anterograde is 2x faster than retrograde
- Supporting Cells: neuron consist ½ the volume of the CNS, rest are
Glia: surround neurons and hold them in place, control their
supply of nutrients, exchange messages with other neurons,
destroy died neuron.
o Three type of Glia cells
Astrocytes: star shape
Provide physical support to the neuron
Clean up debris within the brain
Produce chemical that neuron need
Control the chemical composition of fluid
Provide nutrients to neurons. Somatic and
dendritic membrane are surrounded by
astrocytes: take nutrients from the capillaries,
and take off wastes of neurons
Astrocyte receive glucose from the capillaries
and break it down into LACTATE release
lactate in ESF neuron take the LACTATE
transport to Mitochondria use for energy When neuron metabolic rate is high, use
glycogen stored by astrocyte: glycogen
Act as nerve glue
Isolate the synapse and limit the dispersion of
Oligodendrocytes: produce myelin sheath which is 80%
lipid and 20% proteins. They also support the
unmylinated axons Multiple sclerosis can destroy
myelin by activating the autoimmune system.
Sheath formed is not continuous but
segmented with a little segment of uncoated
axon in btw node of RANVIER. AP jump from
node to node
Microglia: smallest of the glia cell, act as phagocyte
and breakdown dead neuron it is the IMMUNE
system of the BRAIN
- Schwann cells: myelin sheath in the peripheral nerves and support
Difference from oligodendrocytes: Oli has several processes wrap
around several axons. In Schwann cell, one cell provide myelin
for one whole axon.
Damage myelin in PNS, it can regrow back. If damage myelin in
CNS, it cannot.
o Axon has 2 modes of regrow:
1 : axon elongate and reach the target
2nd : when reaching the target, axon stops elongate
and give rise to terminals.
o Astrocyte produce scar tissue stop regrow of axon and if no
scar tissue, axons in CNS will start with the 2 ndmode, not
the 1 one. So, axon regrow in PNS and CNS differ in
terms of the supporting cells not the axon itself.
o Immune system in CNS attack OLIGODENDROCYTES only.
protect brain from the outside environment,
semi-permeable to certain substances LACK of gap junction that allow direct exchange from capillary
Maintain a balance in brain fluid and this balance is very
important for messages transmission. Disruption of fluid balance
= disruption of fluid transmission.
Communication within a neuron
- EX: holding a hot pot. Excitatory neurons send the info of dropping the
pot, but inhibitory neuron send the info of holding it finally, we hold the
pot, because the AP generated by the inhibitory neurons are stronger.
Measuring Electrical Potentials of axons: performed with a squid axon
- take a squid axon, put in sea water
- insert an electrode in sea water
- insert a microelectrode in axon
- we measure the membrane potential with oscilloscope: -70mV
- put another microelectrode in axon, send an electrical impulse
- we measure the AP
- when membrane potential return to normal, it overshot, and become
Membrane Potential: this electrical charge is a balance btw diffusion and
molecules diffuse from high concentration to low concentration
- Electrostatic pressure
cation attract anion and cation
- A- and K+ are found in the ICF (inside the cell)
A-: unable to pass through the membrane of axon, contribute to
the resting membrane potential.
K+: diffusion wants K+ to flow to ESF, but electrostatic force
keep K+ inside the cells
- Cl- and Na+ are found in the ECF (outside the cell)
Cl-: diffusion want Cl- go inside the cell, but electrostatic force
keep it in ECF
Na+: both diffusion and electrostatic force want Na+ to go into
ICF, but sodium-potassium keep Na+ concentration in ESF. Pump 3 Na+ out and 2K+ in each time. This require energy.
Membrane is more permeable to K+ than Na+.
an AP will activate the Na+ channels
Na+ merge into the cells
This unbalance of electrical charge cause K+ channels open and
leave the cell
Na+ channels close, no more Na+ come in
K+ channels still open, more K+ leave the cells to get back to -
K+ channels close, Na+ channels reset this correspond the
overshot of membrane potential ( K+ is driven out by diffusion
and electrostatic force)
- those channels are voltage-dependent
- firing rate control the strength of the muscle contraction.
- mylinated axons come into contact with ESF only at node de RANVIER
- AP jump from node to node= saltatory conduction
- when AP propagate down the axon, it get smaller and smaller, this is
called DECREMENT conduction, but it is still enough to trigger AP
- in unmylinated axon, AP remain the same and propagate down.
- myelin and large axon=fast conduction
Communication btw Neurons
- a chemical that attaches to a binding site is called a ligand.
Neurotransmitters are natural ligand, and produced/released by neurons
Structure of Synapse
- synapse can be axodendritic, axosomatic, axoaxonic
- synaptic vesicles are found near the membrane, in the release zone
- type of vesicles:
small synaptic vesicles: produced in Golgi apparatus in the soma
then transported to terminal by FAST axoplasmic transport or it
could by produce in the terminals by using recycled material.
Large synaptic vesicles: only produced in the soma and
transported through by the slow axoplasmic transport
- the postsynaptic membrane are dense and thick than elsewhere
because it has receptors to detect neurotransmitters Release of Neurotransmitters
- AP opens Ca channels
- Ca enter the cell
- entry of Ca cause the fusion pore btw synaptic vesicle and membrane
- neurotransmitters are then released
- Ca entry is critical, if we only have AP but no Ca, neurotransmitters will
not be released.
- three distinct pools of synaptic vesicles
1. Released-ready: ducked against the inside of the presynaptic
membrane, ready to release their content. <1% than total
number of vesicles at terminals
2. Recycling pool: 10-15%
3. Rest are reserve pool.
- The recycling process for 1 is <1sec, for 2