1. The Brain
Unit 3 B

3. The Brain

4. Phineas Gage Video

5. Ways we Study the Brain Accidents Lesions EEG CAT Scan PET Scan MRI
Functional MRI

6. Accidents Phineas Gage Story Personality changed after the accident.
What does this tell us?
That different part of the brain control different aspects of who we are.

8. Lesions Purposeful removal or destruction of some part of the brain.
Frontal Lobotomy

9. Electroencephalogram
EEG
Detects brain waves through their electrical output.
Used mainly in sleep research.

10. Computerized Axial Tomography
CAT Scan
3D X-Ray of the brain.
Good for tumor locating, but tells us nothing about function.

11. CT example

12. Magnetic Resonance Imaging
MRI
More detailed picture of brain using magnetic field to knock electrons off axis. Shows the structure of the brain
Takes many still pictures and turns images into a movie like production.
Does not study function!

13. MRI example
Notice the tumor…

14. Positron Emission Tomography
PET Scan: depicts brain activity by showing each brain areas’ use of its chemical fuel
Measures how much of a chemical the brain is using (usually glucose consumption). Also shows activity of the brain
Good for studying function.

15. PET scan
Depression

17. Functional MRI
Combination of PET and MRI: shows functioning and activity
fMRI is good for function, hence the f.

18. f MRI example
Amygdala activation
Primary Visual
Cortex activation

20. Dr. Jones, a brain researcher, is investigating the connection between certain environmental stimuli and brain processes. Which types of brain scans is she most likely to use?
A. MRI and CAT
B. CAT and EKG
C. PET and fMRI
D. EKG and CAT
E. lesioning and MRI

21. The answer was C. The CAT and the MRI give insight into brain structure, not function.

22. Brain Structures Hindbrain/brain stem Midbrain/limbic system
Forebrain/cerebral cortex
Cerebral cortex is part of forebrain

23. The brain was built
like a house, bottom
to top.
The hindbrain controls
basic functions like breathing. Shared with animals
The forebrain is the
most complex

24. Hindbrain Structures on top of our spinal cord.
Controls basic biological structures.
All animals have hindbrains!
The brain in purple makes up the hindbrain.

25. Medulla Oblongata Located just above the spinal cord.
Involved in control of
blood pressure
heart rate
breathing. (basic stuff!)

26. Pons Located just above the medulla.
Connects hindbrain with midbrain and forebrain. Helps coordinate movements
Involved in facial expressions.
Bladder control, eye movement, posture, hearing and more

27. Cerebellum Bottom rear of the brain. Means “little brain”
Coordinates fine muscle movements and balance. Kicking a goal in soccer

28. What is reticular formation?
Part of brain – affects consciousness. Sleep meds affect this part of the brain. Damage leads to a coma. Controls arousal and ability to focus attention

29. Midbrain
Consists of the thalamus
Cerebellum and the Limbic system

30. Cerebellum

31. The Limbic System deals with memory and emotions

32. Thalamus Switchboard “relay station” of the brain.
Receives sensory signals from the spinal cord and sends them to other parts of the forebrain.
Every sense except smell.

33. Hypothalamus Maybe most important structure in the brain.
Controls and regulates the temperature, hunger, thirst
Controls the endocrine system. All the glands
The most powerful structure in the brain.

34. Rat with an Implanted Electrode in pleasure center of Hypothalamus

35. Ventromedial Hypothalamus
Lateral Hypothalamus
Ventromedial Hypothalamus
When stimulated it makes you hungry.
When lesioned (destroyed) you will never be hungry again.
Larger Hunger
When stimulated you feel fufull.
When lesioned you will never feel fullulagain.
Very Minute Hunger

36. Hippocampus Involved in the processing and storage of memories.
Its proximity to your emotional centers explains why memories and emotions are so linked!

37. http://www. youtube. com/watch

38. Amygdala
Brain part involved in telling your body to produce norepinephrine (adrenaline)
More involved in volatile emotions like anger.
The emotion of anger has not changed much throughout evolution.

39. What is the cerebral cortex?

40. The Cerebral Cortex
Made up of densely packed neurons we call “gray matter”
Wrinkles are called fissures.
If you lay brain out it would be as big as a large pizza.
It’s divided into 2 hemispheres and 4 lobes!
Left and right hemispheres

41. Cerebral Cortex
What makes us human, animals without a large cortex act on instinct
Cc contains billion nerve cells
300 trillion synaptic connections
Glial cells support these nerve cells. Neurons are like queen bees they cannot feed or protect themselves glial cells worker bees they provide nutrients, and insulating myelin, mop up neurotransmitters , chat with neurons

42. The Cerebral Cortex is made up of four Lobes. Label your brain outline!

43. What are Frontal Lobes?
Abstract thought and emotional control and planning.
Contains Motor Cortex, Broca’s area.
Lobotomies damage this.
Suppresses the Amygdala.

44. What is the motor cortex?
Part of the brain in the frontal lobe that tells my body how to move (like typing this).

45. What is the sensory cortex?
It’s the part that deals with touch sensations. It’s
In the parietal lobe.

46. What are Motor and Sensory Cortexes?
The wires are switched! Right controls left!
The motor cortex is in which lobe?

47. Sensory homunculus A visual representation of how much space
your brain needs to operate parts of your body. Notice how big the face and hands are. How small everything else is!

48. Motor strip and homunculus

50. Parietal Lobes
Contain Sensory Cortex: receives incoming touch sensations from rest of the body.
Most of the Parietal Lobes are made up of Association Areas.
Where would this girl feel the most pain from her sunburn?

51. Occipital Lobes Think “optical”.
Contains Visual Cortex: interprets messages from our eyes into images we can understand.

52. Notice how close the auditory cortex is to the ears.

53. Association areas
About ¾ of the brain which is not involved in the sensory or motor activity
Association areas integrate information
These areas link sensory inputs with stored memories –Very important
Found in all 4 lobes
In frontal lob association areas allow us to learn, judge and process new memories but damage would not allow you to plan ahead

54. Association Areas continued
In parietal lobes assoc. areas allow us to use math and spatial reasoning, recognize faces

55. Figure 3B.16 Areas of the cortex in four mammals More intelligent animals have increased
“uncommitted” or association areas of the cortex. These vast areas of the brain are responsible for integrating and acting on information received and processed by sensory areas.
© 2011 by Worth Publishers

56. Temporal Lobes Process sound sensed by our ears.
Interpreted in Auditory Cortex.
NOT LATERALIZED.
Sound goes to both temporal lobes

57. Aphasia- impaired use of language
Broca’s area – production of speech think (boca) (left side of the frontal lobe).Struggle to speak but can sing and comprehend
Angular gyrus- speak and understand cannot read aloud
Wernicke’s area deals with comprehension of language. Speak meaningless words also disrupts comprehension
Which side of brain are we seeing?

58. Aphasia Videos http://www.youtube.com/watch?v=1aplTvEQ6ew

59. Figure 3B.18 A simplified model of brain areas involved in language processing
© 2011 by Worth Publishers

60. Figure 3B.19 Brain activity when hearing, seeing, and speaking words PET scans such as these detect the activity of different areas of the brain.
© 2011 by Worth Publishers

61. Specialization and Integration in Language

62. Brain Activity when Hearing, Seeing, and Speaking Words
Which side of the brain are we seeing?

63. Brain Plasticity
The idea that the brain, when damaged, will attempt to find news ways to reroute messages.
Children’s brains are more plastic than adults.
Neurogenesis- the ability of the brain to make new neurons

64. Video Brain Plasticity

65. Neurons’ ability to re-route their messaging in case of injury.
Brain plasticity
Neurons’ ability to re-route their messaging in case of injury.

66. When brain researchers refer to brain plasticity, they are talking about
A. the brain’s ability to quickly regrow damaged neurons
B. the surface texture and appearance caused by the layer known as the cerebral cortex
C. the brain’s versatility caused by the millions of neural connections
D. our adaptability to different problems ranging from survival needs to abstract reasoning
E. new connections forming in the brain to take over for damaged sections

67. Demonstration: Any volunteers?
What is Split Brain?
Demonstration: Any volunteers?

69. The Corpus Callosum Divides the 2 hemispheres.
Divides the left from right sides.
The corpus callosum
is cut to prevent seizures
from spreading to the other
side of the brain.

70. A Tour Through The Brain: Lateralization
The left and right hemispheres of the
brain each specialize
in particular operations.

71. Figure 3B.22 The information highway from eye to brain Information from the left half of your field of vision goes to your right hemisphere, and information from the right half of your visual field goes to your left hemisphere, which usually controls speech. (Note, however, that each eye receives sensory information from both the right and left visual fields.) Data received by either hemisphere are quickly transmitted to the other across the corpus callosum. In a person with a severed corpus callosum, this information sharing does not take place.
© 2011 by Worth Publishers

72. Split Brain Patients
Those who, due to epilepsy, have their corpus callosum cut or removed.

73. Visual Information
Visual information directed to each side of the brain comes from visual fields not from the eyes. The left eye does not send information to the right hemisphere and vice versa. The RIGHT HALVES of each eye send information to the right hemisphere and vice versa

74. Figure 3B.23 Testing the divided brain When an experimenter flashes the word HEART across the visual field, a woman with a split brain reports seeing the portion of the word transmitted to her left hemisphere. However, if asked to indicate with her left hand what she saw, she points to the portion of the word transmitted to her right hemisphere.
From Gazzaniga, 1983
© 2011 by Worth Publishers

75. A Tour Through The Brain: Split-Brain Research (Continued)

76. Split Brain Video http://www.youtube.com/watch?v=aCv4K5aStdU

77. Experiment #1 Split-brain patients
Experimenter shows fork to left hemisphere (presents to the right side)
Participant is asked what he saw…
He states “fork”
Experimenter shows spoon to right hemisphere
Participant is asked what he saw
Response: “I don’t know”
Participant is asked to reach in a bag with left hand (right hemisphere) to retrieve what he saw
He pulls out a spoon…explain?

78. Other weird issues with split-brain
A split-brain patient was asked what he wanted to do with his life…
Left hemisphere wrote: architect
Right hemisphere wrote: race car driver
Suicide case study
Left hand (right hemisphere) kept trying to strangle herself
Left hemisphere was unaware of why this was happening and had to defend herself
Tumor was discovered on her corpus collosum

79. On the next slide, say the COLOR of the word without reading the word.

81. Right-Left Brain Differences for the rest of us with intact brains
Right Brain:
Perceptual tasks Making inferences
Sense of self
Problem seeing other people in relation to themselves
Cannot recognize themselves in a mirror
Left Brain
Speaks
Calculates
Literal interpretation in language
Sign language included

82. Brain and Consciousness
What is consciousness? Evolutionary psychologist believe it must be involved with reproduction or survival
But how do brain cells talk to one another?
No clue how the brain creates consciousness
Cognitive neuroscience- science of brain activities connected to mental processes

83. Studies show if you imagine doing something an fMRI of your brain indicates activity
We have dual processing- 2 minds operate at the same time conscious mind (explicit) mind and your unconscious mind (implicit)
Much of our thinking operate outside of our awareness