Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
196 Cards in this Set
- Front
- Back
|
Phrenology
|
-physiological functions localized, better function more activity needed, greater the area (bumps on skull)
|
|
|
Phrenology's major contribution
|
ares of brain for different functions
|
|
|
Phineas Gage
|
-metal rod through part of brain responsible for reasoning, and executive functions, changed his personality
|
|
|
Why study brain and behaviour?
|
-many behavioural disorders can be understood or cured by understand the brain
-brain is most complex living organ on earth -how the brain produces both behaviour and human consciousness |
|
|
What is the Brain?
|
-two hemispheres
-cerebral cortex -gyri -sulci -4 lobes |
|
|
Hemispheres
|
brain contains two almost symmetrical hemispheres
|
|
|
gyri
|
bumps on folded structure
|
|
|
sulci
|
grooves on cortex
|
|
|
cerebral cortex
|
heavily folded outer layer of brain tissue compose of neurons
|
|
|
4 lobes
|
-frontal lobe
-occipital lobe -temporal lobe -pariel lobe |
|
|
Gross Structure of Nervous System
|
Central Nervous System (CNS)
Peripheral Nervous System (PNS) |
|
|
Central Nervous System
|
-brain and spinal chord
|
|
|
Peripheral Nervous System
|
all neurons in the body that are located outside the brain and spinal chord
|
|
|
Neuron
|
brain cell engaged in information processing
|
|
|
Sensory Neuron
|
neuron that carries incoming information from sensory receptors in spinal cord and brain
|
|
|
Motor Neuron
|
neuron that carries information from spinal cord to make muscles contract
|
|
|
What Is Behaviour?
|
"patterns in time"
-movements, vocalization, thinking |
|
|
Innate Behaviours
|
relatively fixed, invariant ways of responding
|
|
|
Learned Behaviours
|
flexible ways of responding
|
|
|
Overt Behaviours
|
can see
|
|
|
Covert Behaviours
|
Cannot see
|
|
|
Mentalism
|
-behaviour as function of nonmaterial mind.
-Aristotle -brain cooled the blood, no role in behaviour |
|
|
Brain as a cooling organ?
|
-large number of blood vessels in brain
-brain not responsible for behaviour |
|
|
All in the heart!
|
Aristotle believed the seat of sensations and thoughts is the heart
eg pain and pleasure |
|
|
Dualism
|
-nonmaterial mind and the material body contribute to behaviour
-Descartes -mind directs rational behaviour |
|
|
Mind-body problem
|
quandry of explaining how a nonmaterial mind is in command of a material body
|
|
|
How mind works in Dualism
|
-body and brain direct all behaviours via mechanical and physical principles
-mind is located in pineal gland of the brain, sits beside ventricles filled with fluid -mind regulates behaviour by directing flow of ventricle fluid to appropriate muscles |
|
|
Materialism
|
-behaviour explained as a function of the nervous system
-no recourse to the mind -perspective adopted for the course |
|
|
Natural Selection
|
-explanation for how species evolve and existing species change over time
-variation among individuals in a species -traits that enhance survival and reproduction are more likely to be transmitted -change over generations |
|
|
Natural Selection Implications
|
-since all animal species are related their neurons and their brains are related too, their behaviour is also related
|
|
|
Jerison (1973)
|
Principle of Proper mass
Encephalization Quotient (EQ) |
|
|
Principle of proper mass
|
species exhibiting more complex behaviours will possess relatively larger brains
|
|
|
Encephalization Quotient
|
measure of the brain size obtained from the ratio of actual brain size to the expected brain size for an animal of a particular body size
-homo sapiens have the largest |
|
|
The Brains Primary Functions
|
-creating a sensory reality (evolution has equipped each species with a view of the world that helps it survive)
-Integration of Information (current knowledge can be compared with past knowledge) -Producing Behaviour |
|
|
Two parts of PNS
|
-somatic
-autonomic |
|
|
Somatic nervous system
|
-produces movement
-incoming sensory information |
|
|
Autonomic Nervous System
|
-balances internal organs
|
|
|
Two Types of Nerves
|
Afferent
Efferent |
|
|
Afferent Nerves
|
sensory signals from muscles and skin
|
|
|
Efferent Nerves
|
sensory signals to muscles and skin
|
|
|
Two parts of Autonomic Nervous System
|
Sympathetic
Parasympathetic |
|
|
Sympathetic System
|
-mobilize energy stores
-arousal -fight or flight response |
|
|
Parasympathetic System
|
-conserve energy resources
-relaxation |
|
|
The Spinal Cord
|
-controls most body movements
-can act independently of brain -spinal reflex (patellar tendon) |
|
|
The Brainstem
|
-begins where spinal cord enters the skull
-produces movement and creates a sensory world |
|
|
Three Regions of Brainstem
|
-hindbrain
-midbrain -diencephalon |
|
|
Hindbrain
|
-evolutionarily old part of brain
-control of movement |
|
|
Hindbrain (parts)
|
-cerebellum
-reticular formation -pons -medulla |
|
|
Cerebellum
|
-controls complex movements and has a role in a variety of cognitive functions
-size increases with the physical speed and dexterity of a species |
|
|
Reticular Formation
|
-netlike mixture of neurons and nerve fibres
-"reticular activating system" -stimulates the forebrain - regulation of sleep-wake behaviour and behaviour arousal |
|
|
Pons
|
-connects cerebellum to the rest of the brain
-controls important movements of the body |
|
|
Medulla
|
-vital functions: control of breathing and heart rate
|
|
|
Midbrain (regions)
|
Tectum
Tegmentum |
|
|
Tectum
|
-roof of midbrain
-sensory processing (visual and auditory) -produces orienting movements |
|
|
Tegmentum
|
-floor of midbrain
-eye and limb movement -species specific behaviour -perception of pain |
|
|
Diencephalon (regions)
|
-hypothalamus
-thalamus |
|
|
Hypothalamus
|
-feeding
-sexual behaviour -sleeping -temperature regulation -emotional behaviour -hormone function with pituitary gland |
|
|
Thalamus
|
-sensory processing
-motor processing -integrative functions -motivation -memory -drinking can damage memory part of thalamus |
|
|
The Forebrain (regions)
|
-neocortex
-basal ganglia -limbic system |
|
|
Necortex (function)
|
-regulates various mental activities, more conscious or complex activities
|
|
|
Basal Ganglia
|
-collection of nuclei just below the white matter of the neocortex
-controls voluntary movement -related disorders - parkinsons and tourettes |
|
|
Limbic System
|
-regulates emotions, sexual behaviours, memory and spacial navigation
-group of structures between the neocortex and brain stem |
|
|
The cortex
|
-neocortex
-limbic cortex |
|
|
Neocortex
|
-6 layers of gray matter
-creates and responds to a perceptual world |
|
|
Limbic cortex
|
-3 or 4 layers of gray matter
-controlling motivational states |
|
|
4 major areas of the neocortex
|
-frontal
-parietal -occipital -temporal |
|
|
Frontal lobe
|
-executive functions
-motor functions -memory? -personality |
|
|
Parietal lobe
|
-sensorimotor
-integrates information from visual and motor areas |
|
|
Occipital Lobe
|
-vision
|
|
|
Temporal Lobe
|
-language
-memory |
|
|
Protecting the Brain
|
-skull
-meninges -ventricles -cerebrospinal fluid -blood brain barrier |
|
|
Meninges (3 layers)
|
-dura mater
-arachnoid layer -pia mater |
|
|
Dura Mater
|
"hard mother"
tough outer layer of fibrous tissue of meninges |
|
|
Arachnoid layer
|
"like a spider web"
thin sheet of delicate connective tissue of meninges |
|
|
Pia Mater
|
"soft mother"
moderately tough inner layer of meninges |
|
|
Cerebrospinal Fluid
|
-sodium chloride and other salts
-fills ventricles and circulates the brain -in the subarachnoid space (between arachnoid layer and pia mater) -cushions and supports the brain -continuously replaced -made by choroid plexus |
|
|
Choroid Plexus
|
makes cerebrospinal fluid
|
|
|
Meningitis
|
infection of the meninges and cerebrospinal fluid
|
|
|
Blood Brain Barrier (BBB)
|
-impedes the passage of toxic substances from the blood to the brain
-some molecules are actively transported (glucose) |
|
|
Surface Features of the brain
|
-surface blood vessels
-stroke |
|
|
Surface blood vessels
|
-anterior, middle and posterior cerebral arteries
|
|
|
Stroke
|
sudden appearance of neurological symptoms as a result of severe interruption of blood flow
|
|
|
Internal Features of the brain
|
-gray matter
-white matter -ventricles |
|
|
Gray Matter
|
areas of the nervous system predominately composed of cell bodies and blood vessels
|
|
|
White Matter
|
areas of the nervous system rich with fat-sheathed neural axons
|
|
|
Ventricle
|
a cavity in the brain that contains cerebrospinal fluid
|
|
|
Ventricles
|
-central canal - spinal chord
-cerebral ventricles - 4 large internal chambers of the brain |
|
|
Hydrocephalus
|
-swelling of the head and build up of pressure in the brain caused by a blockage of CSF flow
-can cause brain damage and deficits |
|
|
Two main types of cells in Nervous system
|
Neurons
Glia |
|
|
Neurons
|
-carry out brains major functions
-approx 80 million -functional units -enable us to receive information, process it and act |
|
|
Glia
|
-aid and modulate neuron's activities
-approx 100 billion -glial cells (glue) -help neurons |
|
|
Functions of Glial Cells
|
-structural support
-nutrients -protection |
|
|
Neurons and Behaviour
|
-most behaviours are produced by a group of hundreds or thousands of neurons
-neurons continuously change shape -most neurons stay with you for life and are never replaced |
|
|
Three Basic Subdivisions of the Neuron
|
-dendrites
-cell body/soma -axon |
|
|
Dendrites
|
gather information from other neurons
|
|
|
Cell Body or Soma
|
core region, contains nucleus
integrates the information |
|
|
Axon
|
-carries information to be passed on to the other cells
-Axoplasmic Transmission |
|
|
Dendritic Spines
|
Protrusions from a dendrite that greatly increases the surface area and is the usual point of contact with axons
|
|
|
Axon Hillock
|
juncture of soma and axon where the action potential begins
|
|
|
Myelin Sheath
|
fatty insulating material
|
|
|
Nodes of Ranvier
|
gaps in myelin sheath
|
|
|
Axon Collaterals
|
branch of an axon
|
|
|
Teleodendria
|
branch of an axon collateral
|
|
|
End Foot/Axon Terminal
|
knob at the end of an axon that conveys information to other neurons; also called terminal button
|
|
|
Synapse
|
-gap between one neuron and another neuron
|
|
|
Information flow in neuron
|
Dendrite --> cell body --> axon --> end foot
|
|
|
Excitation and Inhibition
|
-language of neurons
-neurons sum the signals they get |
|
|
Sensory neurons
|
bring information to CNS
|
|
|
Interneurons
|
associate sensory and motor activity within the CNS
|
|
|
Motor Neurons
|
sends signals from the CNS to the muscles
|
|
|
Glial Cells
|
-Ependymal Cells
-Astrocyte -Microglial -Oligodendroglia Cell -Myelin -Shwann Cells |
|
|
Ependymal Cells
|
-small, found in the walls of ventricles
-make and secrete cerebrospinal fluid |
|
|
Astrocyte
|
-star shaped, symmetrical
-structural support for neurons -transports substances between neurons and capillaries -scar tissue formation |
|
|
Microglia
|
-phagocytosis - scavenge debris
|
|
|
Oligodendroglia
|
-glial cell in the CNS that myelinates axons
|
|
|
Myelin
|
glial coating that surrounds axons
|
|
|
Schwann Cells
|
-glial cell in the PNS that myelinates axons
|
|
|
Multiple Sclerosis
|
-nervous system disorder that results from the loss of myelin around axons
-loss of CNS myelin -demyelination causes many areas of hard scar tissue |
|
|
Symptoms of MS
|
-muscular weakness
-numbness -tingling -tremors -ataxia -visual disturbance -urinary incontinence |
|
|
Parts of a Cell
|
-cell membrane
-phospholipids -nucleus -genes -transcription -ribosomes -translation |
|
|
Cell Membrane
|
-separates inter and extra cellular fluid
-regulates movement of substances into and out of the cell |
|
|
Phospholipids
|
-hydrophilic head: phosphorous
-hydrophobic tail: lipids |
|
|
Nucleus
|
-cells executive office
-chromosomes - double helix structure that holds an organisms entire DNA sequence, 23 pairs |
|
|
Genes
|
-contains segments of DNA
-blueprints for making proteins |
|
|
Transcription
|
-early phase of protein synthesis DNA --> RNA
|
|
|
Endoplasmic Reticulum
|
has ribosomes and site of translation
|
|
|
Epigenetics
|
study of changes of gene expression that do not involve changes in the genetic code
|
|
|
Mitochondria
|
-provide biological energy
-use glucose and oxygen to make ATP -found everywhere in neuron |
|
|
Golgi Bodies
|
-package proteins in membranes (vesicles) and give them a label where to go
|
|
|
Microtubules
|
transport the vesicles to where they need to go
|
|
|
How do Neurons send messages?
|
-resting potential
-action potential -change in the electrical potential of the cells membrane |
|
|
Resting/Membrane Potential
|
-60mv --> -70mv
|
|
|
Cell Membrane (voltage)
|
-all cells maintain an electrical potential at rest of -70mv
-due to the presence of ions, cations and anions |
|
|
Extracellular Fluid (Ions)
|
-high concentration of Na and Cl
|
|
|
Intracellular Fluid (Ions)
|
high concentration of K
|
|
|
Diffusion
|
Concentration gradient
|
|
|
Electrical
|
opposites attract
|
|
|
Ion Channel
|
-opening in a protein embedded in the cell membrane that allows the passage of ions
|
|
|
Ion Gate
|
-proteins embedded in a cell membrane that allows substances to pass through membrane on some occasions but not others
|
|
|
Ion Pump
|
-protein embedded in a cell membrane that actively transports a substance across the membrane
|
|
|
Resting Potential
|
-the point at which the forces drawing ions outside the cell are balanced by forces keeping ions inside the cell
|
|
|
Action Potential
|
-how axons communicate with other neurons b/c they lead to the release of neurotransmitters
|
|
|
Graded Potential
|
-small voltage fluctuations int he cell membrane
-restricted to the vicinity on the axon where ion concentration changes |
|
|
Hyperpolarization
|
-increase electrical change (more negative)
-usually due to the inward flow of chloride ions or outward flow of potassium |
|
|
Depolarization
|
-decreases in the electrical charge (more positive)
-usually due to inward flow of sodium |
|
|
The Action Potential
|
-large, brief reversal in polarity of an axon
-lasts approx 1 millisecond -the result of the cell membrane changing its permeability to certain ions - |
|
|
Threshold
|
-voltage at which an action potential is triggered
-opening of the Na and K voltage sensitive channels -approx -50mv |
|
|
Refractory Periods
|
-a period at which no other APs can be produced - absolute refractory period
-a period of time where a stronger than normal voltage will trigger APs - relative refractory period |
|
|
The Nerve Impulse
|
-propagation of an action potential on the membrane of an axon
-refractory periods create a single, discrete impulse that travels only in one direction -size and shape of an action potential remains constant along the axon |
|
|
Action Potential Speed
|
-the speed of an AP influences the rate with which an animal can react to certain stimuli
|
|
|
Is Bigger Better? (axons)
|
-larger diameter neurons transmit APs faster than smaller
|
|
|
Why are mammalian axons smaller?
|
-myelin acts as insulator and increases the speed
|
|
|
Nodes of Ranvier (AP speed)
|
-small breaks
-sites of impulse generation -high density of Na channels |
|
|
Saltatory Conduction
|
-appears current jumps from node to node
-propagation of an AP at adjacent nodes of Ranvier -"saltare" to dance |
|
|
Graded Potentials
|
-minor hyperpolarizations or depolarizations
|
|
|
Postsynaptic/Graded Potentials
|
Excitatory Postsynaptic Potentials
Inhibitory Postsynaptic Potentials |
|
|
Excitatory Postsynaptic Potentials (EPSP)
|
-brief depolarization of a neuron membrane in response to stimulation
-neuron is more likely to produce an action potential -Result from Na entering the cell |
|
|
Inhibitory Postsynaptic Potentials (IPSP)
|
-brief hyperpolarization of a neuron membrane in response to stimulation
-neuron less likely to produce an action potential -occurs when synaptic input opens the gates for more K ions to leave the cell or more Cl ions to enter |
|
|
Summation of Inputs
|
-EPSP and IPSPs are summated
-Temporal Summation -Spatial Summation |
|
|
Temporal Summation
|
graded potentials that occur at approximately the same time on a membrane are summated
|
|
|
Spatial Summation
|
graded potentials that occur at approximately the same location on a membrane are summated
|
|
|
Neurotransmitter (def)
|
chemical released by a neuron onto a target with an exitatory or inhibitory effect
|
|
|
Neurotransmission steps
|
Step 1 - Synthesis and Storage
Step 2 - Release of the Neurotransmitter Step 3 - Activation of Receptor Sites Step 4 - Deactivation |
|
|
Neurotransmission - Synthesis and Storage
|
-axon terminal - building blocks from food are pumped into cell via transporters
-cell body - according to instructions in DNA, transported on microtubules to axon terminal |
|
|
Neurotransmission - Release
|
-AP opens voltage-sensitive calcium channles
-Ca enters the terminal and binds to the protein calmodulin forming a complex -complex causes some vesicles to empty their contents into the synapse |
|
|
Calmodulin
|
protein that binds with calcium in neurotransmission
|
|
|
Neurotransmission - Activated Receptors
|
-neurotransmitters diffuse across the synapse and activates receptors on the postsynaptic membrane
-neurotransmitter may cause an EPSP or IPSP, or initiate other chemical reactions that modulate either the excitatory or inhibitory effect |
|
|
Transmitter - Activated Receptors
|
-protein embedded in the membrane of a cell that has a binding site for a specific neurotransmitter
|
|
|
Neurotransmission - Deactivation
|
-at least 4 different ways
-diffusion -degradation by enzymes -reuptake by presynaptic neuron -taken up by neighbouring glial cells |
|
|
Varieties of Neurotransmitters
|
-about 50 million different kinds identified
-some can be both inhib and excit -more than one neurotransmitter may be active at a single synapse |
|
|
Identifying Neurotransmitters
|
-synthesized or present in the neuron
-when released, must produce a response in a target cell -same response must be obtained when chemical is experimentally placed on target -must be mechanism for removal |
|
|
Three Groups of Neurotransmitters
|
Small Molecule Transmitters
Peptide Transmitters Transmitter Gases |
|
|
Small Molecule Transmitters
|
-quick acting
-synthesized in the axon terminal from products of diet |
|
|
Peptide Transmitters
|
-neuropeptide
-multifunctional chain of amino acids that act as a neurotransmitter -synthesized from mRNA on instructions from the cell's DNA -do not bind to ion channels, do not have direct effects on the voltage of the postsynaptic membrane |
|
|
Transmitter Gases
|
-synthesized in cell, as needed
-easily crosses cell membrane |
|
|
Ionotropic Receptors
|
-embedded membrane protein with two parts 1. binding site for neurotransmitter 2. a pore that regulates ion flow to directly and rapidly change membrane voltage
|
|
|
Receptors for Direct and Indirect Effects
|
Metabotropic Receptors
Second Messengers |
|
|
Metabotropic Receptors
|
-embedded membrane protein with a binding site for a neurotransmitter but no pore
-linked to a Gprotein that can affect other receptors or act with second messengers to affect other cellular processes |
|
|
Second Messenger
|
-activated by a neurotransmitter (first messenger)
-a chemical that carries a message |
|
|
Dorsal
|
top
|
|
|
Ventral
|
bottom
|
|
|
Medial
|
middle
|
|
|
Lateral
|
toward side
|
|
|
Anterior
|
front
|
|
|
Posterior
|
back
|
|
|
Fissures
|
very deep sulci
|
|
|
Tracts
|
collections of fibres found within the CNS
|
|
|
Law of Belle and Magendie
|
dorsal fibres afferent, ventral fibres efferent
|
|
|
8 Principles of the Nervous System Function
|
-The Sequence of Brain Processing is In-->Integrate --> Out
-Sensory and Motor Divisions Exist Throughout the Nervous System -Many of the Brain's Circuits are crossed -The Brain is both Symmetrical and Asymmetrical -The Nervous System works through Excitation and Inhibition -The CNS Functions on Multiple Levels -Brain Systems are Organized both Hierarchically and in Parallel -Functions in the Brain are both Localized and Distributed |
|
|
Types of Sensory Neurons
|
bipolar neuron
somatosensory neuron |
|
|
Bipolar Neuron
|
retina of eye, single short dendrite and single short axon
|
|
|
Somatosensory Neuron
|
brings sensory information from body into spinal cord, dendrite directly to axon, cell body to side
|
|
|
Types of Interneurons
|
-pyramidal cells
-purkinje cell |
|
|
Pyrimidal Cell
|
long axon, pyramid shaped body, two sets of dendrites, carry info from cortex to the rest of the brain and spinal cord
|
|
|
Purkinje Cell
|
pyramidal cell with extremely branched dendrites, carries info from cerebellum to rest of brain and spinal cord
|
|
|
Motor Neurons (structure)
|
extensive network of dendrites, long cell bodies, and long axons
|
