1. The Central Nervous system
The Body’s Processing Centre

2. Work your Brain
Complete the back side of the brain teasers from last week’s class
Can you decipher #31?!?
Stroop test
Test your short-term memory at
Watch part of Bozeman science podcast at: (to 3min45sec)

3. Case Study: Phineas Gage
The strange but true story of a 25-year old railway construction foreman
September 1848
Textbook p. 432

4. The Nervous System Split into 2 parts: 1. Central nervous system
The structural & functional core of the nervous system
Is the processing centre for the body
Receives info from sensory neurons
Evaluates the information
Initiaties a response by sending signals to muscles and glands via the PNS
Composed of the brain and spinal cord
2. Peripheral nervous system
Composed of sensory (receptor) and motor (effector) pathways

5. Body Worlds Exhibit

6. Differences in Complexity

7. Evolution of vertebrate brain
Shark
Frog
Cat
Bird
Human
Spinal cord
Hind: Medulla oblongata
Optic tectum
Hind: Cerebellum
Midbrain
Fore: Cerebrum
Olfactory tract
Crocodile
forebrain
forebrain dominant cerebrum
hindbrain
forebrain

8. Nervous system
Central nervous system
Peripheral nervous system
Spinal cord
Sensory pathways
Motor pathways
Brain
Somatic (voluntary) system
Autonomic (involuntary) system
Sympathetic division
Parasympathetic division

9. Types of neurons sensory neuron interneuron motor neuron cell body
axon
interneuron
dendrites
dendrites
cell
body
motor neuron

10. The Crucial Organ: The Brain
Processes and interprets incoming stimuli and information
Relays a message or causes a response
Directs all bodily functions
Divided into lobes

11. Did you know? The average brain weighs about 3 lbs
The brain is the fattest organ in the body
Your brain is about 75% water
There are about 100 billion neurons in the brain alone
Most of these neurons are interneurons
There are anywhere from 1,000 to 10,000 synapses for each of these interneurons
The brain consumes about 20% of the oxygen and food contained within blood
The cerebrum composes about 85% of the whole human brain

12. The Brain’s Protection
Despite its central importance, the brain is super fragile and has a Jello-like consistency
Implications for concussions and chronic traumatic encephalopathy (CTE)
Skull forms a bony, protective armour around the brain
Meninges are 3 layers (dura, arachnoid, pia) of tough, elastic tissue that encase the brain and spinal cord
Cerebrospinal fluid (CSF) is a dense, clear liquid that acts as a shock absorber
Located between arachnoid & pia mater layers

13. 3 Main Divisions of The Brain

14. Hindbrain, Midbrain, ForeBrain
Hindbrain  cerebellum, brainstem (medulla oblongata & pons)
Responsible for coordination and movement
Midbrain
Processes sensory input
Forebrain  cerebrum, thalamus, hypothalamus
Regulates thought, learning, and emotion

15. Major Brain Structures
Cerebrum
Thalamus
Hypothalamus
Cerebellum
Brain stem II
III IV V

16. Cerebrum Most highly evolved structure of mammalian brain
Composed of 2 hemispheres
left  controls right side of body
right  controls left side of body
Corpus callosum is the major connection between the hemispheres
Folds & grooves greatly increase surface area and ability to do work
Divided into lobes

17. Lateralization of Brain Function

18. Cerebral Lobes
Regions of the cerebrum are specialized for different functions
4 Lobes
Frontal  front
Temporal  side
Parietal  top back half
Occipital  back bottom portion

19. Somatosensory Cortex in the Parietal Lobe
The main sensory receptive area for the skin

20. Brain Anatomy Cerebrum Corpus callosum Cerebellum Pons Medulla

21. Lateral View of the Cerebrum

22. Cerebral Lobes Carry out sensory and voluntary motor functions
Responsible for higher mental processing
4 lobes
Use your textbook or online sources to find out what each lobe is responsible for
Make your own note

23. Function of Each Lobe Frontal
Voluntary muscle movement, speech, reasoning, problem solving, emotions, personality
Parietal
Receive and process sensory information from the skin (pressure, temperature, pain)
Process info responsible for spatial awareness
Occipital
Vision
Temporal
Auditory processing (hearing, speech)
Verbal memories
Phineas Gage

24. Cerebral Cortex
The outermost layer of gray matter making up the superficial aspect of the cerebrum
Cerebral Cortex

25. Name the Lobes Frontal lobe Parietal lobe Temporal lobe Cerebellum
Occipital
lobe
Temporal lobe
Cerebellum

26. Thalamus At base of the forebrain
Relay station between spinal cord and cerebrum
Receives sensory impulses from receptors
Sorts and files information like a secretary

27. Hypothalamus Lies just below the thalamus
Critical in homeostatic feedback loops
Regulates BP, heart rate, body temperature
Controls basic drives (hunger, thirst) and emotions (fear, rage, pleasure)
Links nervous and endocrine systems

28. Midbrain
Processes info from sensory neurons in the eyes, ears and nose
Relays visual and auditory info between the forebrain and hindbrain
Controls eye movement and skeletal muscle

29. Hindbrain Controls the autonomic system
Regulates breathing, coughing, vomiting, etc.
Activates the brain to maintain arousal or reduces arousal for sleep

30. Cerebellum 2nd largest region of the brain
Coordinates muscle movement, balance, and posture

31. Brain Stem Connects the brain and spinal cord
Control center for autonomic activity
2 main regions:
Pons
Medulla oblongata 1. 2.

32. Medulla oblongata & Pons
Both structures found in the brain stem
Controls autonomic homeostatic functions
Heart rate
Blood vessel activity
Depth of breathing, swallowing, coughing
Relays information to & from higher brain centers

33. Reticular Formation
Part of the brain stem that regulates the sleep cycle, among other things
Part of the pons, but not clearly defined as it also has projections into the thalamus and cerebrum
Sleep & wakefulness produces patterns of electrical activity in the brain
recorded as an EEG
most dreaming occurs during REM (rapid eye movement) sleep
EEG = ElectroEncephaloGram

34. Review of the Main Structures of the Brain
1. Cerebrum
2. Corpus callosum
3. Cerebellum
4. Medulla oblongata
5. Spinal cord
6. Pons
7. Hypothalamus
8. Thalamus

35. Limbic system: Your Lizard Brain
Portion of the brain that deals with emotions, mood, memories and arousal
Mediates basic emotions like fear, anger, sadness, etc.
Composed of the:
Hypothalamus  homeostatic control
Hippocampus  involved in the formation of new memories
Amygdala  raw emotions (aggression, fear, arousal, etc.), involved in recognizing facial expressions, possibly anxiety?, sexual orientation??
Cingulate gyrus  pathway to transmit messages

37. Let’s Have Some Fun with That Brain of Yours
Optical Illusions

51. The Spinal Cord Composed of billions of neurons
Acts as a pathway to and from the brain
Located in the vertebral column
Enables reflex actions

52. Cross-Section of the Spinal Cord
Axons run to and from the brain and outward to the body
Peripheral nerves enter and exit through openings in each vertebra
Within each vertebra, each nerve separates into:
dorsal roots  sensory nerves
ventral roots  motor nerves

54. Quiz Time! 6 1 7 8 2 9 3 10 4 5 11

55. Quiz Time! Parietal Lobe Frontal Lobe Corpus Callosum Occipital Lobe
Hypothalamus
Thalamus
Temporal Lobe
Cerebellum
Pons
Medulla Oblongata
Spinal Cord

56. Mammalian Brain
Examine a mammal’s brain and locate as many brain structures as possible
You will need:
Gloves
Dissecting tray
Probe
Goggles
½ sheep brain
Gather your materials and have a look!
Corpus callosum
Cerebrum
Cerebellum
Pons
Medulla

57. Locate the Following Structures
The 3 regions of the brain
Corpus callosum
The 4 cerebral lobes
Brain stem
Cerebellum
Thalamus
Hypothalamus
Pituitary gland
Pons
Medulla
Spinal cord