Physiological Psychology Flashcards
Chapters 4 - 6
Negative Poles
Creates electrons
(higher charge)
Positive Poles
Where electrons flow
(lower charge)
Diffusion
Ion movement from higher to lower concentration randomly
Concentration Gradient
The high concentration of ions in one area that leads to diffusion
Voltage Gradient
Charge difference in flow of connected areas
(Opposites attract, similars repel)
Resting Potential
(about -70mV) charge during no stimulation
Ions in Greater Concentration (Inside)
Potassium & Large Proteins
Ions in Greater Concentration (Outside)
Sodium & Chloride
Hyperpolarization
More (-) electrical charge
Depolarization
More (+) electrical charge
Action Potential
Large, quick change in polarity of an axon
Threshold Potential
Voltage that triggers an action potential
Voltage-Sensitive Ions Channels
Gated protein channels that open / close with specific membrane voltage
(Na+ is more sensitive)
Absolute Refractory Period
(Short Duration) keeps action potentials clearly separated
Relative Refractory Period
Produces another action potential.
Must have a stronger electrical current.
Nerve Impulse
Like a lightning strike. Sudden discharge of electricity
(All-or-None Law)
Saltatory Conduction
Action potential travels down the axon by jumping between the Nodes of Ranvier
Myelin Sheath
Insulating layer around nerves
Nodes of Ranvier
Stepping stones for electrical signals to quickly travel along myelinated axons
ESPS
(Excitatory Postsynaptic Potentials)
Boosts neuron firing
IPSP
(Inhibitory Postsynaptic Potentials)
Acts as brakes.
Maintains balance in neural communication
Temporal Summation
Ex) Single neuron firing rapidly, building up its effect over time
Spatial Summation
Several neurons working together to influence a single postsynaptic neuron
Otto Loewi’s Research
(Neurotransmission)
Chemicals play a role in nerve impulse transmission
Neurotransmission
Chemicals that cause an inhibitory & excitatory effect
Messenger that transmits signals between neurons
Electrical Synapse v. Chemical Synapse
Electrical: fast
Chemical: more flexible
Neurotransmission
(Synthesize & Store)
Created in the cell body, then, packed into vesicles in the axon terminal
Neurotransmission
(Release)
An influx of calcium triggers the release of neurotransmitters from vesicles
Neurotransmission
(Receptor-Site Activation)
Neurotransmitters move across the synapse & bind to receptors = excitatory or inhibitory effects on the postsynaptic neuron
Neurotransmission
(Deactivation)
Diffusion: spreads out & disappears
Degradation: Breaks down
Reuptake: recycled back into neuron
Astrocyte Uptake: nearby astrocyte absorbs it to release them later
Excitatory Synapse
Facilitates Firing
Inhibitory Synapse
Regulates / prevents excessive neural activity
Identify Neurotransmitters
- Synthesize in neuron
- Active = produced / released due to specific targets
- # 2 response obtained when chemical is experimentally placed on target
- Must have mechanism to remove chemical post-work
4 Classes of Neurotransmitters
(Small-Molecule)
Communication at chemical synapses