Unit 4: parts of the brain and nervous system Flashcards
Nervous system
network of nerves that control and regulate all bodily functions
Nerves
bundles of neurons
Central nervous system
Brain and spinal cord
Peripheral nervous system
nerves that connect the brain to the rest of the body
Somatic Nervous system
(part of the peripheral nervous system)
- carries commands for voluntary movement from central nervous system to muscles
- brings sensory input to central nervous system
Automatic nervous system
(part of the peripheral nervous system) operates outside of conscious control to carry involuntary commands to organs, blood vessels and glands
Sympathetic nervous system
prepares body for situations requiring flight or flight responses, such as redirecting energy from non-essential functions
parasympathetic nervous system
controls gland and organs during calm periods and returns the body back to resting state; responsible for nutrient storage repair, and growth
Endocrine system
network of glands (hormone secreting organs) that work with the CNS and PNS
Hormone
blood borne chemical messengers that are slower than CNS transmissions but travel over greater distances
adrenal hormones
produced by adrenal glands that are located on top of the kidneys, releases adrenaline and cortisol in stressful situations
Pituitary gland
master gland that directs the function of all other glands
Oxytocin
hormone released by the pituitary gland that stimulates uterine contractions during birth, can help induce labour, promotes lactation, and is thought to play a role in social bonding
Spinal cord
(part of the central nervous system)
major bundle of nerves connecting the brain to the rest of the body
spinal reflexes
response to stimuli that is initiated by the spinal cord without involvement from the brain. (ie. response to painful stimuli)
Brainstem
- lowest region of the brain that sits on top of the spinal cord
- where spinal nerves and most cranial nerves connect
- regulates vital functions (damage to this area is often lethal)
- contains the midbrain, pons, and medulla
Medulla
part of the brainstem
- responsible for: hear rate, blood pressure, reflexes such as coughing and swallowing
Pons
part of the brainstem
- responsible for breating, balance, coordination, and relaying sensations (hearing and taste) to higher levels of the brain (pons = bridge)
reticular formation
part of the brainstem
- responsible for arousal (not the sex kind), attention, and wakefulness
Midbrain
part of the brainstem
- responsible for orientation towards salient stimuli, movement, motivation & reward, and downregulation of pain
Cerrebellum
responsible for coordination, balance, precise movement, and accurate timing
Limbic System
often known as the emotional brain but also performs many other important roles
comprised of the hypothalamus, thalamus, amygdala, hippocampus, and basal ganglia
Hypothalamus
part of the limbic system
- interface between brain and body
- responsible for, homeostatic regulation (ie. thirst, hunger), motivation and reward-seeking, flight or fight response, and direction of the autonomic nervous sytstem and the endocrine system
Thalamus
part of the limbic system
relay station for all sensory signals except for smell.
responsible for alertness and conscieousness
Amygdala
part of the limbic system
responsible for: processing emotional significance of sensory info, responding to positive and negative stimuli, creating vivid memories (with hippocampus)
Hippocampus
part of the limbic system
responsible for memory, spatial navigation, and mental time travel.
basal ganglia
part of the limbic system
responsible for: planning, executing, controlling, and suppressing voluntary movement; reward and pleasure
Cerebral Cortex
Outermost and largest part of the human brain
- divided into left and right hemispheres, which are connected by a large bundle of nerve fibres called the corpus callosum. Further divided in five lobes (frontal, parietal, occipital, temporal, and insular)
Frontal lobe
part of the cerebral cortex
responsible for: movement and planning (contains the primary motor cortex which is a map of the body’s muscles), also contains the prefrontal cortex
prefrontal cortex
part of the frontal lobe
responsible for: executive function, planning, judgement, decision-making, and the conscious experience of emotions
Parietal Lobe
part of the cerebral cortex
contains the primary somatosensory cortex (map of the skin surface) which allows us to process touch
responsible for: paying attention to and locating objects, navigating surroundings
Occipital lobe
part of the cerebral cortex
responsible for: vision, interpreting input from eyes by responding to basic info about image (ie shading, edges, colour)
contains the primary visual cortex.
temporal lobe
part of the cerebral cortex
responsible for: hearing and understanding language, recognizing objects and people
contains: primary auditory and olfactory cortexes
Association cortex
integrates incoming info from sensory areas with existing knowledge to create a meaningful understanding of the world
Insular Lobe
part of the cerebral cortex
responsible for: precieving the state of internal organs (ie. racing heart)
contains: primary taste cortex
Primary Sensory Areas
First cortical areas to receive signals from their associated sensory nerves
Corpus Callosum
bridge of fibres that connect the two cerebral hemispheres and allow them to talk to each other (process called interhemispheric transter)
Contralateral Organization
while both hemispheres are involved in receiving sensory info and sending motor commands, they each do so for the opposite side of the body
Lateralization
some functions are located on either the right or the left side
- areas in the left hemisphere are specialized for language while the analogous areas in the right side are specialized for nonverbal and visuospatial processing of information
Broca’s Area
Wernicke’s Area
Phrenology
19th century belief that all mental faculties and characteristics correspond to specific parts of the brain and can be determined by examining indentations on the skull (not true)
lesion
abnormal tissue resulting from disease, trauma, or surgery
Single and Double dissociation
single: lesion to brain structure A disrupts function X but not Y
double: lesion to brain structure A disrupts function X but not Y. Lesion to brain structure B disrupts function Y but not X
Deep brain stimulation
stimulating specific parts of the brain with implanted electrodes, can be used for treatment of disorders such as depression
Transcranial Magnetic Stimulation (TMS)
exposure to magnetic field to create temporary disruption or enhancement of cortical brain function (limited spatial precision)
Transcranial Direct Current Stimulation (TDCS)
low levels of direct current delivered via electrodes on the head to stimulate brain function (limited spatial precision)
Positron Emission Tomography (PET)
uses an injection of a radioactive tracer (glucose) that is taken up by brain tissues during a task, and traces radiation emitted from the tracer
Functional Magnetic Resonance Imaging (FMRI)
measures brain activity by detecting changes in blood oxygenation with magnets -> when the brain is more active, it needs more oxygen
Neural plasticity
the brain’s ability to adapt throughout a person’s life
neurogenesis
the generation of new neurons in specific parts of the brain due to stimulus
Critical Period
timeframe during development when the brain is extra receptive to environmental stimuli, which allows for larger changes in neural connections
Damage plasticity
neural modification/reorganization following an injury
