* a stimulus triggers a nerve in the peripheral nervous system (pns) which sends a neural impulse...
TRANSCRIPT
*Our Brain
*Neural Processing
*A stimulus triggers a nerve in the Peripheral Nervous System (PNS) which sends a Neural Impulse (Action Potential) through the PNS towards the Central Nervous System (CNS)
*Once the NI enters the Spinal Cord it ascends towards the brain where it enters the Brain Stem
*The Thalamus, acting like a conductor, sends the NI to the area of the brain for processing
*Neurons
*A nerve cell
*Dendrites
*A bushy branching extension
*Receives messages from other neurons and conducts impulses toward the cell body
*Axon
*Extension of a neuron, ending in branching Terminal Fibers
*NI’s passed to other neurons
*Myelin Sheath
*Layer of fatty tissue encasing the Axon
*Helps speed the transmission of the NI
• Degeneration of the MS
• Delays the transmission of NI’s
*Action Potential
*Neural Impulse
*A brief electrical charge that travels down an Axon
*Synaptic Gap
*Gap between Axon Terminal of one neuron and the Dendrites of another neuron
https://www.youtube.com/watch?v=TW6v96zzOZM
*Human Brain activity is
measured in thousandths of a
second, computers in a
billionth
*The Nervous System
*The body’s speedy electrochemical communication
network•Peripheral Nervous System (PNS)•Central Nervous System (CNS)
*PNS
*Sensory and Motor Neurons that connect the CNS to the rest of the body
*Two sub-systems
*Somatic Nervous System (SNS) and Autonomic Nervous System (ANS)
*SNS
*Voluntary control of skeletal muscles*https://youtu.be/8_RfK2rp2To?t=18
*ANS
*Glands and muscles of internal organs; glandular activity, heartbeat, digestion*I want you to think about your heart right now, is it beating?
*367/6=*61.7
*Two sub-systems
*Sympathetic NS and Parasympathetic NS
*SympNS
*Arouses and expends energy
*Accelerated heart rate, blood pressure increases, releases adrenaline
*Parasymp
*Conserves energy and calms HR and lowers blood pressure
*CNS
*Brain
*Spinal cord
l
*40 billion neurons that connect to 10,000 neurons individually= 100 trillion synapses*If you were to spend $20 a second it would take you 23,120 days to spend $40 billion
*Spinal cord: ascending neural fibers send sensory info, descending NF’s send back motor control info
*Reflexes
*Automatic responses to a stimuli
*Test our reflexes
*Partner up
*Stopwatch
*Ruler
*Record
*How do scientists study the internal brain?
*Electroencephalogram (EEG)
*Amplified recording of the waves of electrical activity that sweeps across the brain
*Positron Emission Tomography (PET)
*Visual display of where the brain is consuming fuel (glucose) during a given activity
*Magnetic Resonance Imaging (MRI)
*Magnetic fields and radio waves used to produce images of soft tissue
Think of as a picture
*functional MRI
*Mapping blood flow in the brain, when multiple images are viewed in succession it shows brain function
*https://www.youtube.com/watch?v=9IK2eDh3cVs
Think of as a movie
• You want to learn about seizures, a disorder caused by a sudden, extreme rise in neural impulses=• (EEG)
• You want to see how much energy is consumed by the brain when someone is reading versus reciting a memorized passage=• (PET)
• You want to see where Alzheimer’s affects the speech area of the brain=• (MRI)
• You want to see what areas of the brain are used when completing a word search=• (fMRI)
http://www.ted.com/talks/sarah_jayne_blakemore_the_mysterious_workings_of_the_adolescent_brain?language=en#t-7570091.What is the main difference between MRI
and fMRI?
2.What is Synaptic Pruning?
3.What is significant about the increased use of medial prefrontal cortex in adolescents?
4.Why do adolescents take so much pleasure in hyper-risk taking?
Our Brain• About 2% of our body
mass, at 3 pounds• Consumes almost 20% of
our body’s energy
• The social-brain
*The Brai
n Ste
m• Oldest part of the brain
• All mammals have in common
*Medulla
*Base of the brainstem and controls: heartbeat and breathing
*Pons
*Above the Medulla and coordinates movement
*Thalamus
*Top of the Brainstem and acts as the brains “sensory switchboard”
*Info from seeing, hearing, tasting and touch (not smell)
*Sends info to the correct brain structure
https://www.youtube.com/watch?v=snO68aJTOpM
*Cerebellum
*“little brain”
*Controls time judgment, modulates emotions and discriminates sounds and textures, coordinates voluntary movement
*Limbic System
*Boarder between “old brain” and the Cerebral Hemispheres
*Amygdala
*Aggression and fear
*Hypothalamus (“below the Thalamus”)
*Directs eating; drinking; body temperature; linked to emotions and reward
Some scientists believe this is the root of addictive behaviors
*Hippocampus
*Center of emotion; memory and the autonomic nervous system
*Cerebral Cortex
*The body’s ultimate control and information-processing center
*More advanced species have an expanded CC with relaxed genetic controls and increased adaptability
*Glial cells- support, nourish and protect neurons (about 9 times more than neurons)
*Four Lobes make up the CC
*Frontal
*Parietal
*Occipital
*Temporal
*Frontal Lobe
*Judgment
*Planning and processing of new memories
*Personality
*Moral judgment
*Parietal Lobe
*Mathematical and spatial reasoning
*Processes taste, touch and temperature
*Occipital Lobe
*Visual cortex
*R eye=L side
*L eye=R side
*Temporal
*Understand and interpret speech
*Auditory cortex
*R eye=L side
*L eye=R side
We are going to fill out our diagram
*Motor Cortex
*Controls voluntary movement
*R=L
*L=R
• Rear of Frontal Lobe
*Everybody UP!!
Lets take a look at Motor
Function
*Sensory Cortex
*Registers and processes body touch and movement sensations
• Front of Parietal Lobe
