Key terms CNS
Chapter 1:
Aggregate field theory (p. 7) = Flourens has the notion that the whole brain participated in
behavior.
Associationism (p. 12) = When simple ideas interact and become associated with another,
complex ideas and concepts are created in an individual’s knowledge system. Role of
experience. Psychological associations believed that the aggregate of a person’s experience
determined the course of mental development. Any response followed by a reward would be
maintained, and that these associations were the basis of how the mind learned.
Associationism was the prevailing theory for many years, until Hebb emphasized the
biological basis of learning, and Chomsky and Miller realized that associationism couldn’t
explain all learning or all actions of the mind
Behaviorism (p. 12)= Learning is key. Everybody had the same neural equipment on which
learning could build. Brain as a blank slate upon which to build through learning and
experience. Hobbes, Hume, John Stuart Mill.
Cognitive neuroscience (p. 4) = received its name in the late 1970’s. How the brain enables
the mind. Cognition: process of knowing. Neuroscience: the study ow how the nervous
system is organized and functions.
Cytoarchitectonics (p. 9) = how cells differ between brain regions. Cellular architecture.
Empiricism (p. 11)= The idea that knowledge comes from sensory experience, that the brain
begins life as a blank slate. Direct sensory experience produces simple ideas and concepts.
Things have to be observable.
Montreal procedure (p. 13)= (Herbert Jasper & Penfield) treating epilepsy; surgically
destroying neurons in the brain that produced seizures. Stimulating various parts of the brain
with electrical probes and observing results on the patients. Creating maps of the sensory
and motor cortices in the brain, confirming the topographic predictions.
Neuron doctrine (p. 10) = (Ramon y Cajal) The concept that the nervous system is made up of
individual cells. The transmission of electrical information is only in one directions, from
dendrites down to the axonal tip.
Phrenology (p. 6) = Anatomical personolgy. Gall. Localizationist view of the brain.
Rationalism (p. 11) = All knowledge could be gained through the use of reason alone; truth is
intellectual, not sensory. Rationalism considers such issues as the meaning of life, whereas
logic does not. Logic relies simply on inductive reasoning, statistics, probabilities, and the like.
Descartes, Spinoza, Leibniz.
Syncytium (p. 9) = Golgi believed that the whole brain was a continuous mass of tissue that
shares a common cytoplasm.
Big questions:
o Why were the ancient Greeks important to science?
o What historical evidence suggested that the brain’s activities produce the mind?
o What can we learn about the mind and brain from modern research methods?
,Chapter 2:
- Within neuron: info from input synapse to output synapse: electrical flow
- Between neurons: inro across synapses mediated chemically
- More intense stimuli elicit higher action-potential firing rates
Action potential (p. 31) = A rapid depolarization and repolarization of a small region of the
membrane on the neuron’s output via its axon caused by the opening and closing of ion
channels. They enable signals to travel for meters with no loss in signal strength, because
they continually regenerate the signal at each patch of membrane on the axon. All ore none
phenomena.
Amygdala (p. 50)
Association cortex (p. 61) = Nor primary motor cortex nor primary sensory cortex. Contains
cell that may be activated by more than one sensory modality. Receives inputs from many
cortical areas.
Autonomic nervous system (p. 40) = involved in controlling the involuntary action of smooth
muscles, the heart, and various glands. Sympathetic (fight or flight) and parasympathetic
(rest and digest)branches.
Axon (p. 27) = a single process that extends from the cell body. The output side of the
neuron. Electrical signal travel along the length of the axon to it end.
Axon collaterals (p. 27)= Some axons branch to form one. It can transmit signals to more than
one cell.
Axon hillock (p. 32)
Basal ganglia (p. 50) = A collection of nuclei bilaterally located deep in the brain. Receives
inputs from sensory and motor areas, and the striatum receives extensive feedback
projections from the thalamus. Subcortical nuclei: the caudate nucleus, putamen, globus
pallidus, and substantia nigra, subthalamic nucleus. Action selection, gating, motor
preparation, timing, fatigue, task switching. Many dopamine receptors. Reward-based
learning and goal-oriented behavior.
Blood–brain barrier (BBB) (p. 24): Barrier between tissues of the CNS and the blood. Restricts
the diffusion of microscopic objects (bacteria) and large hydrophilic molecules in the blood
from entering the neural tissue. Allows diffusion of small hydrophobic molecules like oxygen,
CO2 or hormones. Large role in protecting the CNS from blood-borne agents and pathogens.
Brainstem (p. 46) = having 3 main parts; the medulla, the pons and cerebellum, the midbrain.
Form the CNS between the spinal cord and the diencephalon. Contains groups of motor and
sensory nuclei, widespread modulatory neurotransmitter systems and white matter tracts of
ascending sensory information and descending motor signals. Damage to the brainstem is
life-threating.
Central nervous system (CNS) (p. 40) = The brain and spinal cord
Central sulcus (p. 54) = divides the frontal lobe from the parietal lobe
Cerebellum (p. 42) = Little brain; highly layered, containing billions of neurons. Information
about motor outputs and sensory inputs describing body position. Inputs involved in balance
as well as auditory and visual inputs. Critical for maintaining posture, walking and performing
coordinated movements.
Cerebral cortex (p. 42) = has billions of neurons. Is arranged in a sheet containing several
layers of neurons, folded across the surfaces of the cerebral hemispheres. A thin grayish
layer overlying a whitish interior.
, Commissure (p. 42) = Axons may project from one cerebral hemisphere to other in bundles.
Largest is the corpus callosum.
corpus callosum (p. 42)
Cytoarchitectonics (p. 54) = uses the micro anatomy of cells and their organization; the
brain’s microscopic neuronal architecture- to subdivide the cortex.
Dendrites (p. 26) = Branching extensions of the neuron that receive inputs from other
neurons.
Depolarization (p. 32) = When membrane is less than -55Mv. A change within a cell, during
which the cell undergoes a shift in electric charge distribution, resulting in less negative
charge inside the cell compared to the outside
Electrical gradient (p. 30) = A force created by difference in inside and outside voltages.
Electrotonic conduction (p. 31) = Passive current conduction. Also decremental conduction. It
diminishes with distance from its origin. Communication will fail.
Equilibrium potential (p. 32) = the membrane potential at which there is no net flux of a
given ion. As a result the membrane is temporarily hyperpolarized.
frontal lobe (p. 53)
Glial cell (p. 24) = Providing various functions like structural support and electrical insulation
to neurons and modulating neuronal activity.
Astrocytes: create the BBB between tissues of the central nervous system and the blood.
+ role in brain function: Neuronal activity moderation (regulation of reuptaking
neurotransmitters).
Oligodendrocytes: from myelin (in CNS), Schwann cells in PNS. Is a good electrical
insulator, preventing loss of electrical current across the cell membrane. Increases the
speed and distance that info can travel along the neuron
Microglial cells: small and irregularly shaped. Phagocytes that devour and remove
damaged cells. Can proliferate even in adults.
Gray matt er (p. 42) = neuronal cell bodies
Gyrus (p. 52) = Infroldings of the cortical sheet. The crowns of the folded tissue that are
visible on the surface.
Hippocampus (p. 50) =
Hyperpolarization (p. 32) = when the membrane has a equilibrium potential and is about -
80mV. It causes K+ channels to close, in response to which the membrane potential gradually
returns to its resting state.
Hypothalamus (p. 49)= Main link between the nervous system and the endocrine system.
Hormone production and control. One of it jobs is to control circadian rhythms with inputs
from the mesencephalic reticular formation, amygdala and retina. The pituitary gland is
attached to the base of the hypothalamus. Also controls the functions necessary for
maintaining the normal state of the body; temperature and metabolic rate, glucose and
electrolyte levels, hormonal state, sexual phase, and immune regulation. It can be stimulated
by hormones circulating in the blood that were produced in other regions of the body.
Insula (p. 54) = located between the temporal and frontal lobes, an island of folded cortex
hidden deep in the lateral sulcus.
Ion channel (p. 28) = Proteins with a pore through the center. They allow certain ions to flow
down their electrochemical and concentrations gradients. Passive (always open) or gated
(only open in the presence of electrical, chemical or physical stimuli).
Ion pump (p. 28) = Use energy to actively transport ions across the membrane against their
concentration gradients. Low > higher concentration
Layer (p. 41) = Gray matter; neurons arranged in layers forming a sheet of tissue.
, Limbic system (p. 50) = includes subcortical and cortical structures that are interconnected
and play a role in emotion.
Medulla (p. 46) = Is continuous with the spinal cord. Essential for life. Houses cell bodies of
many of the 12 cranial nerves, proving sensory and motor innervations to the face, neck,
abdomen, and throat, as well as the motor nuclei that innervate the heart. Vital functions
like respiration, heart rate, arousal, digestive and vomiting responses. It is the crossroads for
most of the body’s fibers.
Microcircuit (p. 39) = Localized interconnected neurons form this. They process specific kinds
of information and can accomplish sophisticated tasks such as processing sensory info,
generating movements and mediating learning and memory.
Midbrain (p. 48) = Superior to the pons. It is involve with the processing of anxiety and fear
and is critical for autonomic regulation and for defensive responses.
- Superior colliculus: plays a role in perceiving objects in the periphery and orienting our gaze
directly toward them, bringing them into sharper view.
- Inferior colliculus: locating and orienting toward auditory stimuli.
- Red nucleus: involved in certain aspects of motor coordination.
myelin (p. 25)
Neocortex (p. 55) = Cortex that contains 6 cortical layers or that passed through a
developmental stage involving 6 cortical layers. Includes areas like primary sensory and
motor cortex and association cortex.
Neural network (p. 39) = macro circuits that are made up of multiple embedded
microcircuits. Long-distance connections between various brain regions connect.
Neuron (p. 24) = The basic signaling units that transmit information throughout the nervous
system. By changes in their activity levels, pass the signal along to other neurons or muscles.
They vary in their form, location, and interconnectivity within the nervous system. > related
to their functions.
Neurotransmitter (p. 35) = A molecule which:
Is synthesized by and localized within the presynaptic neuron, and stored in the
presynaptic terminal before release
Is released by the presynaptic neuron when action potentials depolarize the terminal
The postsynaptic neuron contains receptors specific for it.
Neurotransmitters must be removed from the receptor after binding. This removal can
be accomplished by active reuptake back into the presynaptic terminal, enzymatic
breakdown of the transmitter in the synaptic cleft, or diffusion of the neurotransmitter
away from the region of the synapse.
Node of Ranvier (p. 32) = Regular intervals along the axon where gaps in myelination occur.
Nucleus (p. 41) = A relatively compact arrangement of nerve cell bodies and their
connections, ranging in size from hundreds to millions of neurons with functionally similar
inputs and outputs. Located throughout both the brain and the spinal cord
Occipital lobe (p. 54)
Parietal lobe (p. 54)
Peripheral nervous system (PNS) (p. 40) = the nerves (bundles of axons and glial cells) and
ganglia (clumps of nerve cell bodies outside the CNS)
Permeability (p. 29) = The extent to which a particular ion can cross the membrane through a
given ion channel.
Pituitary gland (p. 49) = In connection with the hypothalamus
Pons (p. 47) = Latin for bridge. Main connection between the brain and the cerebellum.
Made up of a vast system of fiber tracts interspersed with nuclei. Including cranial nerves