1. Chapter 2: Brain and Behavior

2. Chapter topics Neurons – Building a Biocomputer
The Nervous System – Wired for Action
Research Methods – Charting the Brain
The Cerebral Cortex- My, What a Big Brain you have!
The Subcortex – At the Core of the Matter
The Endocrine System – Hormones and Behavior
Psychology in Action – Handedness

3. Building a “Biocomputer”
Neurons
Building a “Biocomputer”

4. How do nerve cells operate and communicate?

6. Neuron and Its Parts Neuron: Individual nerve cell
Dendrites: Receive messages from other neurons
Soma: Cell body; body of the neuron
Axon: Fiber that carries information away from the cell body of a neuron
Axon Terminals: Branches that link the dendrites and somas of other neurons

7. The Nerve Impulse
Resting Potential: Electrical charge of an inactive neuron
Threshold: Trigger point for a neuron’s firing
Action Potential: Nerve impulse
Negative After-Potential: A drop in electrical charge below the resting potential

11. Synapse
Microscopic gap between two neurons over which messages pass

14. Neurotransmitters
Chemicals that alter activity in neurons; brain chemicals
Acetylcholine: Activates muscles
Dopamine: Muscle control
Serotonin: Mood and appetite control
Receptor Site: Areas on the surface of neurons and other cells that are sensitive to neurotransmitters

15. "To learn is to change. Education is a process that changes the learner."
George Leonard

16. "Not choice, but habit rules the unreflecting herd."
~William Wordsworth

17. Plasticity Capacity of the brain to change in response to experience
And, the capacity for routine

18. Neurogenesis
Production of new brain cells

19. The Nervous System
Wired for Action

20. Neural Regulators
Enkephalins: Relieve pain and stress; similar to endorphins
Endorphins: Released by pituitary gland; also help to relieve pain
Neuropeptides: Brain chemicals that regulate the activity of neurons

21. Nerves and Neurons Nerves: Large bundles of axons and dendrites
Myelin: Fatty layer of tissue that coats axons
Neurilemma: Thin layer of cells wrapped around axons outside brain and spinal cord; forms a tunnel where damaged fibers go as they repair themselves

22. Multiple Sclerosis (MS)
Occurs when immune system attacks and destroys myelin layer in the individual’s body; numbness, weakness, and paralysis occur

23. Central Nervous System
Central Nervous System (CNS): Brain and spinal cord

24. Peripheral Nervous System
All parts of the nervous system outside of the brain and spinal cord
Somatic System: Links spinal cord with body and sense organs; controls voluntary behavior
Autonomic System: Serves internal organs and glands; controls automatic functions such as heart rate and blood pressure

27. Two Divisions of the Autonomic System
Sympathetic Nervous System: Arouses body; emergency system
Parasympathetic Nervous System: Quiets body; most active after an emotional event

29. The Spinal Cord
Spinal Nerves: 31 of them; carry sensory and motor messages to and from the spinal cord
Cranial Nerves: 12 pairs that leave the brain directly; keep entire body in communication with your brain

30. Reflex Arc
Simplest behavior; when a stimulus provokes an automatic response

32. Research Methods
Charting the Brain

33. Brain Imaging
Computed Tomographic Scanning (CT): Computer-enhanced X-ray image of the brain or body
Magnetic Resonance Imaging (MRI): Uses a strong magnetic field, not an X-ray, to produce a 3D image of the brain or body
Functional MR (fMRI)I: MRI that records brain activity
Positron Emission Tomography (PET): Computer-generated color image of brain activity, based on glucose consumption in the brain

34. Researching the Brain Ablation: Surgical removal of tissue
Deep Lesioning: A thin wire electrode is lowered into a specific area inside the brain. Electrical current is then used to destroy a small amount of brain tissue.
Electrical Stimulation of the Brain (ESB): When an electrode is used to activate target areas in the brain
Electroencephalograph (EEG): Detects, amplifies, and records electrical activity in the brain

39. My, What a Big Brain You Have!
Cerebral Cortex
My, What a Big Brain You Have!

40. Cerebral Cortex Outer layer of the cerebrum
Cerebrum: Two large hemispheres that cover upper part of the brain
Corticalization: Increase in size and wrinkling of the cortex
Cerebral Hemispheres: Right and left halves of the cortex
Corpus Callosum: Bundle of fibers connecting cerebral hemispheres

42. Split Brains
Corpus Callosum is cut; done to control severe epilepsy (seizure disorder).
Result: The person now has two brains in one body.
This operation is rare and is often used as a last resort

45. Central Cortex Lobes Occipital: Back of brain; vision center
Parietal: Just above occipital; bodily sensations such as touch, pain, and temperature
Temporal: Each side of the brain; auditory and language centers
Frontal: Movement, sense of smell, higher mental functions
Contains motor cortex; controls motor movement

48. Association Cortex
All areas of the cerebral cortex that are not primarily sensory or motor in function

49. Aphasia
Speech disturbance resulting from brain damage

50. Broca’s Area
Language area in brain related to grammar and pronunciation
If damaged, person knows what s/he wants to say but can’t say the words

51. Wernicke’s Area Related to language comprehension
If damaged, person has problems with meanings of words, NOT pronunciation

52. Facial Agnosia
Inability to perceive familiar faces

54. At the Core of the (Brain) Matter
Subcortex
At the Core of the (Brain) Matter

55. Subcortex All brain structures below cerebral cortex
Hindbrain (Brainstem): Lowest portions of the brain; includes cerebellum, medulla, pons, and reticular formation

57. Cerebellum
Located at base of brain; regulates posture, muscle tone, and muscular coordination
Also stores memories related to skills and habits

58. Medulla
Connects brain with the spinal cord and controls vital life functions such as heart rate and breathing

59. Pons (Bridge) Acts as a bridge between medulla and other structures
Influences sleep and arousal

60. Reticular Formation (RF)
Lies inside medulla and brainstem
Associated with alertness, attention and some reflexes (breathing, coughing, sneezing, vomiting)

61. Reticular Activating System (RAS)
Part of RF that keeps the cortex active and alert
Its alarm clock

62. Limbic System
System within forebrain closely linked to emotional response
Thalamus: Relays sensory information to the cortex; switchboard
Hypothalamus: Regulates emotional behaviors and motives (e.g., sex, hunger, rage, hormone release)
Amygdala: Associated with fear responses
Hippocampus: Associated with storing memories; helps us navigate through space

64. Endocrine System
Glands that pour chemicals (hormones) directly into the bloodstream or lymph system

65. Pituitary Gland Regulates growth via growth hormone
Too little growth hormone means person will be smaller than average
Hypopituitary Dwarfs: As adults, perfectly proportioned but tiny
Too much leads to giantism
Excessive body growth

66. Acromegaly Enlargement of arms, hands, feet, and facial bones
Too much growth hormone released late in growth period
Andre the Giant

67. Pineal Gland Regulates body rhythms and sleep cycles
Releases hormone melatonin, which responds to daily variations in light

68. Thyroid In neck; regulates metabolism
Hyperthyroidism: Overactive thyroid; person tends to be thin, tense, excitable, nervous
Hypothyroidism: Underactive thyroid; person tends to be inactive, sleepy, slow, obese

70. The Adrenal Glands
Arouse body, regulate salt balance, adjust body to stress, regulate sexual functioning; located on top of kidneys.
Releases epinephrine and norepinephrine (also known as adrenalin and noradrenalin).
Epinephrine arouses body; is associated with fear.
Norepinephrine arouses body; is linked with anger.

71. The Adrenal Medulla
Source of epinephrine and norepinephrine

72. Adrenal Cortex Produces hormones known as corticoids
Regulate salt balance
Deficiency in some types will cause powerful salt cravings
Oversecretion of adrenal sex hormones can cause virilism: exaggerated male characteristics (Bearded woman)
May also cause premature puberty (full sexual development in childhood) if occurs early in life

73. If Your Brain is Right What is Left?
Psychology in Action
If Your Brain is Right What is Left?

74. Handedness Preference for right or left hand
Dominant Hemisphere: Applies to side of person’s brain that produces language
Lateralization: Difference in the abilities of the brain’s hemispheres