Chapter 2 - Biology of the Mind Flashcards
Dendrite
Receives info and conducts impulses toward the cell body. Short in length. They “listen”.
Axon
Long fiber that sends message through its terminal branches to other neurons, muscles or glands. They “speak”
Myelin Sheath
Layer of fatty tissue that encase some axons to insulate and speed up their impulses. Happens until you are 25, when neural efficacy, judgement and self-control grow. If it degenerates multiple sclerosis results (loss of muscle control).
Phrenology
Franz Gall said that studying peoples bumps on their heads could reveal their mental ability and character traits.
Glial Cells
“worker bees”. They support, nourish and protect neurons. Play a role in learning, thinking, memory. “chatting” with neurons.
Action Potential
A quick electric charge that travels down an axon.
Ions
Electrically charged atoms
Refractory Period
A period of inactivity after a neutron has fired.
Threshold
The level of stimulation required to trigger a neural impulse
All-or-none response
A neurons reaction of either firing or not.
Synapse
Meeting point between the axon tip of the sending neuron and the dendrite of the of the receiving neuron.
Synaptic Gap
The tiny gap in the synapse
Neurotransmitter
Chemical messenger that crosses the synaptic gaps between neurons. They travel across the synapse and bind to receptor sites on the receiving neuron.
Reuptake
A neurotransmitter’s reabsorption by the sending neuron
Acetylcholine (ACh)
Neurotransmitter that plays a role in learning and memory. Messenger between every junction between motor neurons and skeletal muscles. When ACh is released the muscle contracts. If ACh transmission is blocked, it results in being paralyzed. Deterioration of ACh producing neurons results in Alzheimer’s disease.
Motor Neurons
Carry info from the brain and spinal cord to the body’s tissues
Dopamine
Influences movement, learning, attention and emotion. Oversupply - Schizophrenia. Undersupply - tremors and loss of motor control in Parkinson’s disease.
Serotonin
Affects mood, hunger, sleep and arousal. Undersupply-depression. Anti-depressents can raise serotonin levels.
Norepinephrine
Helps control alertness and arousal. Undersupply - depresses mood.
GABA
A major inhibitory neurotransmitter. Undersupply - seizures, tremors, insomnia.
Glutamate
A major excitatory neurotransmitter involved in memory. Oversupply- Over stimulates the brain (migraines or seizures). Why some people avoid MSG in food.
Endorphins
neurotransmitters that are linked to pain control and pleasure.
Agonist
A molecule that increases a neurotransmitters action
Antagonists
A molecule that inhibits or blocks a neurotransmitters action
Nervous system
Speedy electrochemical communication network. All the nerve cells of the peripheral and central nervous systems.
Central Nervous System
Brain and Spinal Cord. The boys decision maker
Peripheral Nervous System
Two components. Somatic and Autonomic. Connect the CNS with the rest of the body
Nerves
Bundled axons that form neural cables connecting the central nervous system with muscles, glands and sense organs.
Sensory Neurons
Carry messages from the body’s tissues and sensory receptors to the brain and spinal cord for processing.
Motor Neurons
Carry instructions from the brain and spinal cord out to the bodys muscles and glands
Interneurons
Neurons within the brain and spinal cord that communicate internally and process info between the sensory inputs and motor outputs.
Somatic nervous system
within the peripheral system that controls the voluntary control of our skeletal muscles.
Autonomic Nervous system
“Self regulating”. Within the peripheral system that controls the glands and muscles of the internal organs. Influences glandular activity, heartbeat and digestion.
Sympathetic nervous system
Within the autonomic nervous system that arouses the body and expends energy. Fight or Flight.
Parasympathetic nervous system
Within the autonomic nervous system conserves energy to calm you
Spinal Cord
Two-way info highway connecting the peripheral nervous system and the brain
Endocrine system
the body’s slow chemical communication system; a set of glands that secrete hormones into the bloodstream
Hormones
Chemical messengers manufactured by the endocrine glands, travel through the bloodstream, and affect other tissues
adrenal glands
endocrine glands that are just above the kidneys and secret hormones (epinephrine and norepinephrine) that help arouse the body in times of stress. it increases heart rate, blood pressure and blood sugar providing energy.
pituitary gland
the endocrine system’s most influential gland. Controlled by the hypothalamus. It regulates growth and controls other endocrine glands
Oxytocin
enables contractions associated with birthing, milk flow during nursing, and orgasms. It promotes pair bonding, group cohesion, and social trust.
feedback system
brain - pituitary - other glands - hormones - body and brain
lesion
tissue destruction. naturally or experimentally caused destruction of brain tissue
EEG
recording of the waves of electrical activity going across the brains surface. measured by electrodes placed on the scalp
PET scan
visual display of the brain activity that detects where a radioactive form of glucose goes while the brain performs a given task
MRI
uses magnetic fields and radio waves to produce computer generated images of soft tissue. shows brain anatomy
fMRI
reveals blood flow and shows brain functions as well as structure
brainstem
the oldest part and central core of the brain, beginning where the spinal cord swells as it enters the skull. responsible for automatic survival functions. the crossover point where most nerves to and from each side of the brain connect with the bodys opposite side
medulla
base of the brainstem, controls heart beat and breathing.
pons
just above the medulla. helps coordinate movement and control for sleep
thalamus
on top of the brainstem, the brains sensory control centre except smell. directs messages to the cortex and transmits replies to the cerebellum and medulla. like a bus station for information to pass through
reticular formation
inside the brainstem between your ears, a neuron network that extends from the spinal cord through the thalamus. controls arousal
cerebellum
“little brain” that enables nonverbal learning and skill memory. helps us to judge time, modulate our emotions and discriminate sounds and textures. with assistance from pons it coordinates voluntary movement. under alcohols influence coordination suffers. if you injured it you would have difficulty walking, keeping your balance, or shaking hands. movement would be jerky and exaggerated
limbic system
amygdala, hypothalamus, and hippocampus; associated with emotion and drives
hippocampus
processes conscious, explicit memories. if hippocampus is lost a person loses their ability to form new memories of facts and events
amygdala
two lima bean sized neural clusters linked to aggression and fear. linked to emotion
hypothalamus
below the thalamus. deals with hunger, thirst, body temperature and sexual behaviour. together, they help maintain a homeostatic state. helps govern the endocrine system through the pituitary gland. linked to emotion and reward.
cerebral cortex
a thin surface layer of interconnected neural cells covering the cerebral hemispheres; the bodys ultimate control and info processing center
frontal lobes
behind your forehead; involved in speaking and muscle movements and in making plans and judgements
parietal lobes
at the top and in the back. receives sensory input for touch and body position
occipital lobes
back of your head on the bottom. receives info from the visual fields
temporal lobes
just above your ears at the temple. auditory areas each receiving info from the opposite ear
motor cortex
at the rear of the frontal lobes that controls voluntary movements
somatosensory cortex
at the front of the parietal lobes that deals with body touch and movement sensations
association areas
area of the cerebral cortex that is involved in higher mental functions such as learning, remembering, thinking, and speaking. found in all four lobes.
prefrontal cortex
in the forward part of the frontal lobes that enables judgement, planning and processing of new memories.
What happened to phineas gage?
He had frontal lobe damage. his mental abilities and memories were intact, but his personality was not.
underside of right temporal lobe
association area that helps us to recognize faces. if this was damaged you would be able to recognize gender or facial features but unable to identify who the person is.
