Unit 2: Biology, Neutrons, And Brain Imagery Flashcards
Dendrites
Branching extinctions that receive incoming messages and conduct messages toward the cell body
Soma
Cell body which contains the nucleus
Biological psychologists study the link between:
1) biology
2) behavior
The basic building block of the nervous system
Neuron or nerve cell
Axon
Extension of a neuron which takes messages from the soma to other neurons; is the longest part of the neuron.
Terminal buttons
Aka axon terminals
Releases neurotransmitters to communicate with other neutrons
Located on the end of the axon
Myelin Sheath
Allows faster transmission speeds in neurons
A layer of fatty cells segmentally encasing the fibers of many axons
How does a neutron communicate?: action potential
Considered an ALL OR NOTHING response
Positively charged
Happens or doesn’t happen
How does a neutron communicate?: resting potential
Refers to the neuron when it is not active
Negatively charged inside the cell membrane
Waiting for gun shot in the race
Threshold
Minimal level of stimulation required for a neural impulse to fire.
Signal fires or doesn’t
Neuron communication with other neurons: synapse
To communicate it must pass a junction or gap called the synapse between the axon which is sending the signal and the dendrite which is receiving the signal
Neuron communication with other neurons: neurotransmitters
Chemical messengers that bind together neurons and influence whether another neural impulse will take place.
At the end of the axon, terminal buttons release these
Pre-synapse and postsynapse
Pre- sender
Post- receiver
Process of reuptake
Excess neurotransmitters are reabsorbed back into the sending membrane (presynaptic)
Types of neurotransmitters: acetylcholine
Most well known for its presence in allowing muscle contraption
Also: plays vital role in learning and memory
KARATE CHOP
Acetylcholine may lead to
Alzheimer’s disease (memory defect) or muscular disorders
Types of neurotransmitters: serotonin
Impact on mood
Happy or sad
Shortage of serotonin
Depression
Types of neurotransmitters: dopamine
Attention
Involuntary muscle movements
Addiction
Excess Dopamine may lead to
Schizophrenia: hallucinations, too much attention
Defect to Parkinson’s disease: start to shake
Types of neurotransmitters: norepinephrine
Increased heart rate
Helps control alertness and arousal when you are scared or stressed or excited
Types of neurotransmitters: endorphins
Aka morphine within
Link to pain control and pleasure
Natural pain reliever
Mimicked by opiates like heroine
Types of Neurotransmitters: GABA
Helps relax and calm down the body.
Shortage- anxiety or epilepsy
Types of signals: excitatory
“pushing accelerator” for action potential
Types of signals: inhibitory
“pushing break” for resting potential
Types of neurotransmitters: glutamate
Excitatory neurotransmitter that helps strengthen the synaptic connections between neurons
Agonist
Chemicals that mimic the effects of a neurotransmitter
Example of agonists
Heroin- agonist for endorphins
MDMA- agonist for serotonin
Alcohol- Agonist for GABA
Antagonists
Chemicals that block the transmission of an neurotransmitter
Example of an antagonist
Chemical in a black widow spider bite is an antagonist for acceleration
Why are many disorders of the brain difficult to treat?
The brain blood barrier (BBB) filters out the unwanted chemicals in the brain
Nervous system
Your electrochemical communication center
Nervous system consists of
1) central nervous system and the nerves within your
2) peripheral nervous system
2 Divisions: CNS
Central nervous system contains
1) brain 2) spinal chord
2 divisions: PNS
Peripheral nervous system: contains the sensory and motor neurons that connect the CNS to the rest of the body.
PNS is divided into
Autonomic
and Somatic
3 types of neurons: sensory neurons (AKA Afferent Neurons)
Neurons that carry info from the sensory receptors (in PNS) to th brain and spinal cord (in CNS)
Sensory neurons example
Touch, feel, smell, see, taste
3 types of neurons: Interneurons
Neurons within the CNS that internally communicate between sensory and motor neurons
Interneurons
Reflexes
3 types of neurons: motor neurons (AKA Efferent neurons)
Take information from the CNS to the muscles and glands within the PNS.
Efferent neurons example
Any type of movement after thinking
Automatic actions=
Are simple reflexes
Reflex
A simple autonomic, inborn response to a sensory stimulus. Spinal cord in charge and brain NOT involved.
Reflex involves in
Interneurons only
How to study the brain: Lesion
Natural or experimentally damaged tissue of the brain used to study portions of the brain
Electroencephalogram (EEG)
An amplified recording of the waves of ELECTRICAL ACTIVITY that SWEEP ACROSS THE BRAIN’s surface
EEG is measured by
Electrodes placed on the scalp
EEG used in
Sleep study
Studying the brain: PET (positron emission tomograph) scan
A visual display of brain activity that detects where a RADIOACTIVE FORM OF GLUCOSE goes while the brain performs a given task
When does PET show brain activity
When doing mental tasks
Studying the brain: MRI (magnetic resonance imaging)
A technique that uses MAGNETIC FIELDS AND RADIO WAVES to produce computer-generated images that distinguish among different types of soft tissues
What does MRI allow
See structures within the brain
FMRI: functional MRI
Reveals blood flow
Hormones
Enter through blood stream
Adrenal glands
Endocrine glands above the kidneys that secrete the hormones epinephrine (adrenaline) and norepinephrine (noradrenaline), which help to arouse the body in times of stress
The endocrine system
The body’s “slow” chemical communication system
What does the endocrine system do?
Secrets hormones into the bloodstream
Hormones travel via
Blood stream
How quick do hormones last?
20-30 minus
Hormones: how long does the effect last?
Long time
Neurotransmitters travel via
Synapse
How quick do neurotransmitters last
Immediately
How long does the effects of neurotransmitters last?
Short time
