Class Notes (784,733)
Canada (481,323)
Psychology (2,565)
PSYC 1001 (304)
Lecture

Psyc 1001G.docx

5 Pages
57 Views
Unlock Document

School
Carleton University
Department
Psychology
Course
PSYC 1001
Professor
Kavita Prakash
Semester
Winter

Description
th Psyc 1001G – Neurons/Nervous system – Jan 29 2013 - Neurons relay messages. Neurons – individual cells in the nervous system that receive and transmit information. - 1. Soma = cell body (nucleus) - 2. Dendrites = receive information from other neurons (“branches” of the cell) - 3. Axon = tube like structure, carries information from cell body to another neuron - 4. Myelin Sheath = it speeds up rate of transition, fatty substance on axon. In multiple sciroses the myelin sheath is damaged – have trouble with motor control - 5. Terminal Buttons = small knobs at end of axon that secretes neurotransmitters. - 6. Neurotransmitters = chemicals that provide messages - 7. Synapse (synaptic gap) = (Neurons do not touch) the synapses is the point at which neurons meet/”connect”. Glia Cells - Glue that holds everything together - Provide support - Smaller in size than neurons - 10:1 ratio compared to neurons - They remove waste (dead neurons) - They compose the myelin sheath (fatty layer on the axon) - Development of Nervous System in embryo (in the 2 trimester – glia plays hug role in brain and nervous system of the child) - Linked to Alzheimer’s disease The Neural Impulse - The electrochemical reaction that moves through the neuron o You can measure this - Ions o Positive (Sodium and Potassium) and negative (Chloride) charges - Neuron has a lot of negative within the membrane – there is a gradient between the system and environment - Resting state = stable, negatively charges of -70 millivolts when at rest (Resting potential) o More negative in the inside when in this state Activation Potential - Stimulation causes cell membrane to open briefly o Different neurons used for different funtions (touch, taste smell ect) - Cell membrane in this case opens up o Chandelles state to open. o Cell becomes more positive in the inside + o K o goes in, Na goes out - Depolarization - Positively charged sodium ions flow in Sift in electrical charge travels along neuron - The Action potential – Shift in neurons electrical charge - All or None Law – Neuron fires or it doesn’t - Refractory Period – no action potential can occur (very short amount of time) The Synapse - Point at which neural impulse travels from one neuron to another - Point of communication between neurons - There is the pre and post - Synaptic Cleft = microscopic gap - Presynaptic neuron = sending signal down axon - Postsynaptic neuron = receiving signal at dendrite When a Neurotransmitter binds: The Postsynaptic Potential - Voltage charge at receptor site – Postsynaptic potential (PSP) - Excitatory PSP = stimulating firing of neuron - Inhibitory PSP = stops the neuron form firing Neurotransmitters - Specific neurotransmitters work at specific synapses (they will work on certain locations) o Lock and Key mechanism – It has to be a perfect fit. In depression there might be to much or too little of a neurotransmitter. Drug that mimic neurotransmitters (such as dopamine) wi Video notes - CNS (nerve pathways) - The brain – cerebral cortex (two parts)  Sensory cortex and motor cortex (pain)  Hippocampus - connects the two sides of the brain  Reward pathway activated by drugs (pleasurable feelings) o Axons ends at a terminal o Exocytosis – secretion of neurotransmitters into the membrane of the dendrite nodes o Receptors sodium ions enter the cell when the neurotransmitters attach to the receptor and open channels o Acetylcholin…. destroys acytle coline. o Dopamine is produced by G –protein –AMP?? o Dopamine is not destroyed – taken up by uptake pumps (proteins), packed in vesicles and reused Drugs and the Brain - Drugs come from plats mainly - In tobacco – nicotine: goes from smoke –> lungs –> blood stream –> brain. o Nicotine competes with acytyl coline and wins – large current is produced across the neurons – Caudate nucleus is affected (involuntary movements occur – tremors) - Coca plant – cocaine : blood vesicles – heart – brain. o Diffuses easily into the brain from the blood stream. It works on dopamine  g protein  AMP. Cocaine binds here and prevents the function of the uptake pumps making them stop functioning. In result the dopamine is more present in synapse; reacts with its receptors causing over stimulation of the neurons. Individuals can suffer from cocaine censures where they suffer from irregular heartbeats which lead to fatal results. …. Neurotransmitters contin
More Less

Related notes for PSYC 1001

Log In


OR

Don't have an account?

Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


OR

By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.

Submit