neuroscience Flashcards
Distinctive feature of neurons
Ability to communicate with other cells
Transmission of information across relatively long distances
Myelin sheath
Improves the efficiency of neural transmissions
Also called the white matter
Only found in nervous system of higher animals
Damage to myelin sheath can be tragic and severe
Resting stat
State in which there is a negative electrical charge of about −70 millivolts within a neuron
Action potential
Electric nerve impulse that travels through a neuron’s axon when it is set off by a “trigger”
Positive electrical charge of about +40 millivolts within a neuron
Speed at which an action potential travels along an axon is determined by the:
Axon’s size
Thickness of the myelin sheath
Neurons differ in terms of:
Quickness of an impulse moving along the axon
Potential rate of firing
Excitatory message:
a chemical message that makes it more likely that a receiving neuron will fire and an action potential will travel down its axon.
Inhibitory message
a chemical message that prevents or decreases the likelihood that a receiving neuron will fire.
synthesis:
transmitter molecules are formed inside the neuron
storage
transmitter molecules are stored in synaptic vesicles which are chambers within axon terminals.
release
When released form presynaptic (sending) neuron, transmitter molecules move from synaptic vesicles across the gap
binding
transmitter molecules bind themselves to receptor sites in the postsynaptic (receiving) neuron
transmitter molecules bind themselves to receptor sites in the postsynaptic (receiving) neuron
Receiving neurons awash, in a continual chemical bath
Producing constant stimulation or constant inhibition of the receiving neurons
Effective communication across the synapse would no longer be possible
Reuptake
Reabsorption of neurotransmitters by a terminal button
Spinal cord:
Bundle of neurons that leaves the brain and runs down the length of the back
Main means for transmitting messages between the brain and the body
Controls simple behaviors on its own, without any help from the brain
Sensory (afferent) neurons
Transmit information from the perimeter of the body to the central nervous system
Motor (efferent) neurons
Communicate information from the nervous system to muscles and glands
Somatic division
Specializes in the control of voluntary movements and the communication of information to and from the sense organs
Autonomic division
Controls involuntary movement of the heart, glands, lungs, and other organs
Controls involuntary movement of the heart, glands, lungs, and other organs
prepares the body for action in stressful situations, engaging all the organism’s resources to respond to a threat.
Parasympathetic division
acts to calm the body after an emergency has ended.
Hindbrain contains:
Medulla: Controls a critical body functions, such as breathing and heartbeat
Pons: Bridge in the hindbrain
Acts as a transmitter of motor information
Involved in regulating sleep
Cerebellum: Part of the brain that controls bodily balance
Cerebellum
Motor-coordination Centre
Concerned with muscular movement coordination, learning, and memory
Regulates complex movements that require precise timing
Cerebellum functions are easily disrupted by alcohol
Intellectual functioning.
Reticular formation
A nerve network that extends from the medulla through the pons, passing through the midbrain and the forebrain
The gatekeeper (sleep-wake cycle)
Produces general arousal of the body
Thalamus
Part of the brain located in the middle of the central core that acts primarily to relay information about the senses
***schizophrenia
Hypothalamus
Maintains homeostasis
Produces and regulates behavior that is critical to the basic survival of the species
Eating, self-protection, sex (pleasure centers), body temperature
Reaction to stress
Limbic system
Part of the brain that controls eating, aggression, and reproduction
Includes the amygdala and hippocampus (and hypothalamus)
Plays an important role in emotion, learning, and memory, along with hippocampus
Cerebral Cortex
Responsible for the most sophisticated information processing in the brain
temporal lobe
Auditory area
occipital lobe
visual area
Broca’s aphasia areas of cortex
difficulty speaking.
Wernicke’s aphasia areas of cortex
difficulty understanding others’ speech and in producing language.
Neuroplasticity
the brain’s ability to change throughout the life span through the addition of new neurons, new interconnections between neurons, and the reorganization of information-processing areas.
Hemispheres
symmetrical left and right halves of the brain that control the side of the body opposite to their location.
Left hemisphere tends to process information sequentially, particularly in verbal areas.
Right hemisphere tends to process information globally, particularly in nonverbal areas.
Lateralization
the dominance of one hemisphere of the brain in specific functions, such as language.
Note that the differences are not great, and the two hemispheres work interdependently.
ft hemisphere:
Verbal abilities, speech, mathematical and logical abilities
Aphasia: partial or total loss of the ability to communicate
Results from damage to Broca’s or Wernicke’s
Associated with more positive emotions.
Mode of processing is analytical: processes information bit by bit.
right hemisphere
Spatial relations
Face recognition, cognitive maps
Mental imagery
Musical and artistic abilities
Associated with negative emotions
Tends to be more holistic: It processes information with respect to global patterns
The split brain:
Gives a chance to study the functions of two hemispheres in isolation (Sperry, 1982).
