Monism

The universe exists on one level.

Tinberg's Four Questions

Physiological, Ontologenetic, Evolutionary, Functional

Tinberg's physiological question

How does the machinery work?

Tinberg's ontologenetic question

How does it develop in the industrial?

Tinberg's evolutionary question

What did it come from?

Tinberg's functional question

What is it good for?

Two ethical positions for animal experimentation?

Regulated use: Benefit can justify minimized harm. Abolitionist: Animals hold the same rights as humans, so no use is permissible.

Three R's of ethical animal experimentation?

Reduction: Fewer animals Replacement: Models or alternatives Refinement: Less pain and/or distress

Neurons

Receive information to transmit to other cells, around 16 billion in the cerebral cortex and about 69 billion in the cerebellum.

Camillo Golgi

Developed a silver plate to determine that the brain is a mesh with no separate cells

Santiago Cajal

Used Golgi's method on infant brains to determine cells were actually separate

Cell Structure: M, N, R, ER, M

Membrane: Phospholipid bilayer, protein channels Nucleus: Chromosomes Ribosomes: Build proteins Endoplasmic Rectulum: Ships them Mitochondria: Supplies energy (Have their own genes, inherited maternally)

Parts of a neuron: S, A, PT, D, I

Soma: Cell body Axon: One per cell, constant diameter, can exceed a meter Presynaptic Terminals: Release chemicals Dendrites: Receive, branching Interneuron: Dendrites and axons in one structure

Afferent vs. Efferent

Afferent: Into a structure (Admit) Efferent: Away from a structure (Exit)

Glia: A, M, O/SC

Astrocytes: Shield synapses, synchronize related neurons, dilate vessels Microglia: Immune function, prune synapses, brake activity. (Too few causes seizures) Oligodendrocytes/Schwann Cells: Build myelin

Sodium-Potassium Pump

Protein complex that repeatedly pushes three sodium ions out of the cell and pulls two potassium ions in. Costs continuous energy.

Hyperpolarization

Increased polarization

Depolarization

Decreased polarization

Propagation

At each point along the axon, action potential generates a new one, so it arrives at the brain at full strength

Back-Propagation

Action potential starts in the axon and travels forward, but it also travels backwards into the soma and dendrites.

Absolute refractory period

No stimulus of any strength can produce an action strength potential

Relative refractory period

Stronger than normal stimulus is needed to cause an action potential

Myelin, Nodes of Renvier

Sheath of fat and protein evolved by vertebrates, containing small gaps (NoR) about a micrometer wide

Saltatory conduction

Action potential spike jumps from node to node

Charles Scott Sherrington

Established that neurons communicate along a junction, the synapse

Presynaptic neuron

Neuron delivering a message

Postsynaptic neuron

Neuron receiving a message

Temporal summation

If a second postsynaptic neuron arrives before the first has fully faded, they combine. When enough cross the threshold in succession, they create an action potential.

Graded depolarization

Excitatory postsynaptic potential (EPSP) which results from a sodium ion entering the neuron.

Graded hyperpolarization

Inhibitory postsynaptic potential (IPSP) produced by the flow of negatively charged chloride ions into the cell.

Spatial summation

Two contact points can activate sensory neurons whose axons converge onto a neuron in the spinal cord.

Inhibitory synapses

Input from an axon hyperpolarizes the postsynaptic cell, moving the cell's charge further from the threshold and decreasing the probability of an action potential.

Spontaneous firing rate

Periodic production of action potentials even without synaptic input

Sympathetic Nervous System

Set of nerves that accelerates heartbeat, dilates pupils, and regulates other organs

T.R. Elliott

Found that applying adrenaline to the surface of the heart, stomach, or eyes had the same effect as the sympathetic nervous system.

Synaptic Cleft

Space between presynaptic and postsynaptic neurons

Neurotransmitters/Neuromodulators

Chemicals that a neuron releases at a synapse

Amino Acids, Modified Amino Acids, Monoamines, Neuropeptides, Purines, Gases

Amino Acid: Glutamate, GABA, glycine, aspartate, etc. Modified Amino Acid: Acetylcholine Monoamine: Also modified from amino acids -Indoleamine: Serotonin -Catecholamine: Dopamine, norepinephrine, epinephrine Neuropeptide: Chain of amino acids. Endorphins, Substance P, Neuropeptide Y, etc. Purine: ATP, adenosine Gas: Nitric oxide (NO)

Catecholomines

Compounds that contain a catechol group and an amine group

Acetylcholine

Synthesized from choline

L-dopa

Precursor to dopamine, helps increase the supply of dopamine

Tryptophan

Precursor to serotonin, crosses the blood-brain barrier through a transport system it shares with other large amino acids.

AMPT

Alpha-methyl-para-tyrosine, temporarily blocks the production of dopamine.

Exocytosis

Caused by calcium entry into a cell, causes a burst of release of neurotransmitter from the presynaptic neuron

Ionotrophic effect

Receptor receiving the neurotransmitter rapidly opens a channel. Twists receptor to open its central channel to allow one type of ion through

Channels controlled by a neurotransmitter?

Transmitter-Gated/Ligand-Gated

GABA

Gamma-amino butyric acid, used by most inhibitory ionotropic effects

Metabotropic effects

Sequence of metabolic reactions that produce slow, long-lasting effects at a synapse

G-Protein

Protein coupled to guanosine triphosphate (GTP)

Number of serotonin receptors?

Seven, each with different subtypes. Anti-depressants stimulate serotonin receptor 2A

What do hallucinogens resemble?

Serotonin. Attach to Type 2A receptors and stimulate them longer than normal

Reuptake

A neurotransmitter is taken after activating its receptor. A transmitter protein moves the molecules back into the presynaptic cell

Autoreceptors

Receptors on a presynaptic neuron that give negative feedback by responding to the transmitter released by the neuron. Inhibit further synthesis and release.

Gap Junction

Direct contact point of one neuron with another, enabling electrical transmission.

Hormone

Chemical secreted by cells in one part of the body and conveyed by blood to influence other cells

Pituitary gland

Endocrine gland attached to the base of the hypothalamus

CNS

Central nervous system. Brain and spinal cord

PNS

Peripheral nervous system. Connects CNS to the rest of the body

SNS

Somatic nervous system. Axons conveying messages from sense organs to CNS and CNS muscles. Part of PNS

ANS

Autonomic nervous system. Controls organs. Part of the PNS

ENS

Enteric nervous system. Controls digestive system. Part of the PNS

Dorsal? Ventral?

D: Toward the back V: Toward the stomach

Anterior? Posterior?

A: Toward the front P: Toward the rear

Superior? Inferior?

S: Above I: Below

Lateral? Medial?

L: Toward the side, away from the midline M: Toward the midline, away from the side

Proximal? DIstal?

P: Located close by D: Located far away

Ipsilateral? Contralateral?

I: On the same side of the body C: On the opposite side of the body

Dorsal Root Ganglia

Clusters of sensory neurons outside of the spinal cord

Sympathetic nervous system

Network of nerves that prepare the organs for activity.

Parasympathetic nervous system/Craniosacral system

Facilitates the vegetative, non-emergency responses

Hindbrain

Posterior part of the brain

Brainstem

Medulla, pons, midbrain, and central structure of the forebrain

Medulla Oblongata

Brain structure just above the spinal cord. Could be considered an enlarged extension of the spinal cord

Amygdala

Temporal lobe structure important for evaluating emotional information

Thalamus

Most sensory information goes here to be processed and send as output to the cerebral cortex

Hippocampus

Crucial to memory of individual events, as well as where you are and where you are going

Temporoparietal junction

Area where the parietal lobe and temporal lobe meet, close to the occipital lobe

Precentral gyrus

Posterior portion of the frontal cortex, specifically for the control of fine movements

Default network

Several areas in the prefrontal cortex and the temporoparietal junction. Dominate activity when you don't need to focus on anything specifically.

Ablation

Removal of brain area

Optogenetics

Using light to control a limited population of neurons

Electroencephalograph

Records electrical activity of the brain through electrodes attached to the scalp.

Genes

Units of heredity that maintain their structural identity from one generation to the next. Most come in pairs aligned along chromosomes.

Epigenetics

Studies changes in gene expression

Histones

Bind DNA into a shape like string wound around balls

Neurotrophins

Steer axonal branches in the right direction

Fovea

Specialized area meant for detailed vision

Color constancy

Recognizing colors despite changes in lighting

Soundwaves

Periodic compression of air, water, or other media

Prosody

Conveying emotional information by tone of voice

Planum temporale

Processes the experience of a sound source moving