Chapter 5: Brain And Behaviour Flashcards
Nervous system
CNS
PNS
-sensory connections to receptors in the skin
-motor connections to body muscles
-sensory and motor connections to internal body organs
Central nervous system CNS
Brain and spinal cord; the brain encased by the skull; the spinal cord is encased by vertebrae
Peripheral nervous system PNS
neurons and nerve processes outside CNS
Somatic nervous system
Things you can control, muscles
Automatic nervous system
Breathing, digestive system
Sympathetic nervous system
elevates your energy, adrenaline, stress response; fight or flight, short term
Parasynthetic nervous system
calming system, allows our body to come back down from stressors (fight or flight
Understanding the brain
-Franz Gall and Phrenology ( early study of the brain)
Phrenology- the brain is divided into different regions; and each region is responsible for a different aspect of someone’s personality, the bigger the region the more influential it is. You could tell things about a persons personality based on the shape of their skull
Temporal lobe
auditory (sound) processing, language and long term memory, taste and smell *temporal and frontal, allow you to be who you are
Frontal lobe
planning , organizing, and impulse control; executive function. The origin of all motor control, ex. Hands when writing something
Parietal lobe
touch and spatial awareness(awareness of space around you and what your body is doing), brain damage to this area, causes people to have weird spatial deficits, stroke causes you to have to think all processes through
Occipital lobe
visual processing (processes visual signals) making sense of the signals
Cerebellum
- base of the brain, involved in coordinating motor movements; damage to this causes clumsiness, you may also have speech problems
How many neurons in the brain
Approx 100 billion neurons in a healthy; all neurons are essential
Gyrus
pl. gyri) : hills (bumps on the outer part of the brain)
Suclus
pl. sulci): valley (groove on the outer part of the brain)
Fissure
deep suclus, longitudinal one divides right from left
Cerebral hemispheres
Connects by the corpus callosum (super highway of information between hemispheres
Orientation in the brain
structures toward the brains midline are medial; those located towards the side are lateral
-structures atop the brain or a structure within the brain are dorsal
-anterior is in the front; posterior is back
-structures towards the top of the brain or one of its parts are ventral
Anatomical orientation
Coronal- frontal view
Horizontal- slice the brain horizontally; view from above
Sagittal- cut the brain in half; look from the side
Meninges
three middle
Skull
Dura mater- tough papery covering
Arachnoid membrane
Pita mater- clear outer covering over the brain, closets to the surface
Subarachnoid space- looked like a spiderweb, where the cerebral spinal fluid flows CSF
CSF
circulates/produced within the central nervous system
-protective function; encases the brain and spinal cord so that they are cushioned
- waste removal system
Blood circulation in the brain
-certain elements in blood are essential for brain function ex. Oxygen
-blood brain barrier, only certain things can pass from blood to the brain cells
Ischemic stroke
blockage of blood = lack oxygen to a section of the brain, it kills brain cells in that area; disoriented, slurred speech, will be given a blood thinner
Hemorrhagic stroke
- caused by a ruptured blood vessel or artery, making blood mix with brain cells directly; causes a immune response, in the brain attempt to save itself it can cause more damage.
Histological
the brain is sectioned and sliced postmortem and neuronal loss is examined; if there is damage to the brain you can see it. Most precise way to measure brain damage
PET scanning
neuro imaging, exploit the fact more blood is needed to regions of the brain that are working. Real time measure, taken while someone is doing a simple task, to see certain regions of the brain, abnormalities can be identified, radioactive tracer in blood stream
Functional magnetic imaging fMRI
changes the oxygen content of the blood alter its magnetic properties; the more oxygen content in the blood, that blood is different
Computerized tomography CT scan
x ray passed through the brain at many different angles creating many different images; can identify bleeding in the brain, identify tumours
Static imaging
Magnetic response imaging MRI
more detailed than CT, can identify brain tissue
Electroencephalography EEG
electrical activity in the brain forms different wave patterns, typically used for sleep, measuring the different stage of sleep
Forebrain (cortex)
responsible for most complex behaviours; reasoning, language, what makes individuals unique
Brian stem
- source of much of our unconscious behaviours that are critical for survival; breathing ect sleep stages
Cerebral cortex
Forebrain, thoughts/planning
Pons
Bridge to the cerebellum, allows you to cycle through the different cycles of sleep
Medulla oblongata
Controls heart rate and breathing; if damaged cannot breath on own
Reticular formation
Allows you to become consciously aware that you are aware, wakes you from sleep
Midbrain: hypothalamus
In charge of the release of hormones; sends the signals
Ex. Sense of hunger, a hormone, stress=fight or flight, stress hormone
Midbrain: Thalamus
sensory relay hub; receives a lot of sensory signals
Midbrain: Amygdala
allows for emotional processing, the emotions of an experience; processing other peoples emotions, fearful experiences people respond more to fear; also forms emotional memories of an experience
Midbrain: hippocampus
allows you to form long term memories
Midbrain: basal ganglia
collection of structures; moderates your movements, helps refine the movements; cell loss can result in Parkinson’s, the basal ganglia allows you not to shake and to perform the movements you desire. Reward, involved in drug addiction
Developments of the forebrain
-human brain retains most of the basic features of other less complex mammalian brains; brain size does not automatically make a mammal smarter, its only part of the story
-brain stem
- midbrain
-forebrain
The smallest unit of brain function
Debate in early 1900s; how does the brain achieve what it does and how small does it go
-Camillo Golgi: collection of nerve fibres working in junction with each other, were the smallest unit
-Santiago Ramon y Cajal: believed you could go farther, the fibers are connected to cells, which he called neurons; needed a stain made by camillo golgi, illuminates a part of the neurons
Neurons
Generate an electrical signal, signals allow us to process things
Structure of a neuron: soma
Cell body
Structure of a neuron: Nucleus
Contains DNA
Structure of a neuron: Dendrites
Surrounded the cell body, antenna which allows the neuron to recite signals
Structure of a neuron: Axon
Generates its an electrical signal
typically they only have one
Structure of a neuron: axon terminals
Contains neurotransmitters which change the electrical signal to a chemical signal
Structure of a neuron: myelin sheath
Covering the axon, always white, conduct a very efficient signal down to the length of the axon
Sensory neurons
feeling of something against your skin ect; simplest kind of neuron
Motor neurons
biggest cells bod and biggest axon, does things very fast and very efficiently, ex. in the spinal cord will connect directly to muscle fibers
Pyramidal cells
a lot of signalling in the outer cortex of the brain
Purkinje cell
found in the cerebellum; a lot of branching
Interneurons
act like a go between, passing signals from one neuron to the next
Glial cells
supportive roles for neurons; different types
Glial cells: Astrocytes
reinforcement of the blood vessels and arteries so that they do not burst; actively transport to places they can be used
Glial cells: Microglial
help remove different kinds of by-products and debris, caretaker cell, provide an immune response, they move in to repair damage
Glial cells: Ependymal cells
produce cerebral spinal fluid
Meningitis- can be diagnosed by looking at spinal fluid
Hydrocephalus- product of too much cerebral spinal fluid; can be fatal
Glial cells: oliogodendrocytes
form myelin on the axon of neurons in the central nervous system, ex. If you sever your spinal cord these cells are against that kind of regeneration, it discourages it
Glial cells: Schwann cells
form myelin on the axons of the peripheral nervous system; the cell lays a path out for neurons to remake their connections ex. Finger gets cut off and re attached
