Unit One

1. Epigenetics: How environmental factors (like stress/diet) "switch" genes on or off without changing DNA. (GENE EXPRESSION)

   
   

2. 
   

   Neuroplasticity: The brain's ability to reorganize itself or build new pathways after damage. (ADAPTABILITY)

   
   

3. 
   

   Glial Cells: Cells that support, nourish, and protect neurons. (NEURON SUPPORT STAFF)

   
   

4. 
   

   Reflex Arc: An automatic signal that goes to the spinal cord and back to the muscle before reaching the brain. (BYPASSES BRAIN)

   
   

5. 
   

   Central Nervous System (CNS): The brain and spinal cord; the body's decision-maker. (COMMAND CENTER)

   
   

6. 
   

   Peripheral Nervous System (PNS): The "wires" connecting the CNS to the rest of the body. (BODY'S EXTENSIONS)

   
   

7. 
   

   Afferent (Sensory) Neurons: Neurons that carry incoming info from senses Award the brain. (SENSORY INPUT)

   
   

8. 
   

   Efferent (Motor) Neurons: Neurons that carry outgoing info Exiting the brain to muscles. (MOTOR OUTPUT)

   
   

9. 
   

   Somatic Nervous System: The part of the PNS that controls voluntary skeletal muscles. (VOLUNTARY)

   
   

10. 
    

    Autonomic Nervous System: The part of the PNS that controls involuntary functions (heart, glands). (INVOLUNTARY)

    
    

11. 
    

    Sympathetic Division: Arouses the body for "Fight or Flight" (increases heart rate, dilates pupils). (AROUSAL)

    
    

12. 
    

    Parasympathetic Division: Calms the body for "Rest and Digest". (CALMING)

    
    

II. Neural Firing & Chemistry

14. 
    

    Action Potential: A brief electrical charge that travels down an axon to send a message. (NEURAL IMPULSE)

    
    

15. 
    

    Dendrites: Branching extensions that receive messages from other cells. (LISTENERS)

    
    

16. 
    

    Soma: The cell body; maintains the health of the neuron. (CELL LIFE SUPPORT)

    
    

17. 
    

    Axon: Long fiber that passes messages away from the cell body. (SPEAKER)

    
    

18. 
    

    Myelin Sheath: Fatty tissue layer that insulates the axon and speeds up the signal. (SPEED)

    
    

19. 
    

    Nodes of Ranvier: The gaps in the myelin sheath where the signal "jumps". (SIGNAL GAPS)

    
    

20. 
    

    Synaptic Gap: The tiny fluid-filled space between neurons. (THE GAP)

    
    

21. 
    

    Depolarization: When positive ions rush into the neuron, making it fire. (FIRING)

    
    

22. 
    

    Resting Potential: The state of a neuron when it is charged and ready but not yet firing. (POLARIZED/READY)

    
    

23. 
    

    Reuptake: When the sending neuron reabsorbs leftover neurotransmitters. (RECYCLING)

    
    

24. 
    

    Agonists: Drugs that mimic or enhance a neurotransmitter. (MIMIC)

    
    

25. 
    

    Antagonists: Drugs that block or inhibit a neurotransmitter. (BLOCKER)

    
    

26. 
    

    Acetylcholine (ACh): Enables muscle action and memory; linked to Alzheimer's. (MOVEMENT/MEMORY)

    
    

27. 
    

    Dopamine: Reward, pleasure, and movement; linked to Schizophrenia (too much) and Parkinson’s (too little). (REWARD)

    
    

28. 
    

    Serotonin: Affects mood, hunger, and sleep; linked to depression. (MOOD)

    
    

29. 
    

    Endorphins: Natural painkillers released during exercise or pain. (PAIN RELIEF)

    
    

30. 
    

    GABA: Major inhibitory neurotransmitter; stops the brain from over-firing. (BRAKES/CALMING)

    
    

31. 
    

    Glutamate: Major excitatory neurotransmitter; involved in memory. (GO/EXCITEMENT)

    
    

III. Brain Structures

32. 
    

    Medulla: Controls heartbeat and breathing. (LIFE SUPPORT)

    
    

33. 
    

    Pons: Coordinates movement and controls sleep/dreams. (SLEEP/COORDINATION)

    
    

34. 
    

    Cerebellum: Coordinates balance and voluntary muscle movement. (BALANCE/ATHLETE)

    
    

35. 
    

    Reticular Activating System (RAS): Controls arousal and alertness. (AWAKE/ALERT)

    
    

36. 
    

    Thalamus: The brain's sensory switchboard (all senses except smell). (RELAY STATION)

    
    

37. 
    

    Hypothalamus: Maintains homeostasis (hunger, thirst, body temp) and controls the pituitary. (THERMOSTAT)

    
    

38. 
    

    Amygdala: Linked to emotion, specifically fear and aggression. (FEAR CENTER)

    
    

39. 
    

    Hippocampus: Processes new memories for permanent storage. (MEMORY MAKER)

    
    

40. 
    

    Corpus Callosum: Nerve fibers connecting the two hemispheres. (COMMUNICATION BRIDGE)

    
    

41. 
    

    Frontal Lobe: Planning, decision-making, and voluntary movement. (DECISION MAKER)

    
    

42. 
    

    Parietal Lobe: Processes sensory input for touch and body position. (TOUCH)

    
    

43. 
    

    Temporal Lobe: Responsible for hearing and language. (HEARING)

    
    

44. 
    

    Occipital Lobe: Responsible for visual processing. (VISION)

    
    

45. 
    

    Motor Cortex: Area at the rear of frontal lobe that controls voluntary movement. (MOVEMENT OUTPUT)

    
    

46. 
    

    Somatosensory Cortex: Area at the front of parietal lobe that processes touch. (SENSATION INPUT)

    
    

47. 
    

    Broca’s Area: Responsible for producing speech (Frontal Lobe). (SPEAKING)

    
    

48. 
    

    Wernicke’s Area: Responsible for understanding speech (Temporal Lobe). (COMPREHENSION)

    
    

49. 
    

    Split Brain: Condition where the corpus callosum is cut to stop seizures. (SEPARATED SIDES)

    
    

50. 
    

    fMRI: Shows brain function by tracking blood flow. (FUNCTION/BLOOD)

    
    

51. 
    

    EEG: Measures electrical activity (brain waves). (BRAIN WAVES)

    
    

IV. Sleep & Sensation

52. 
    

    Beta Waves: Brain waves of an alert, waking state. (ALERT)

    
    

53. 
    

    Alpha Waves: Brain waves of a relaxed, awake state. (RELAXED)

    
    

54. 
    

    Delta Waves: Large, slow brain waves of deep sleep (Stage 3). (DEEP SLEEP)

    
    

55. 
    

    REM Sleep: Paradoxical sleep where muscles are paralyzed but brain is active; dreaming occurs. (DREAMS)

    
    

56. 
    

    REM Rebound: Tendency for REM to increase after sleep deprivation. (CATCHING UP)

    
    

57. 
    

    Activation-Synthesis: Theory that dreams are the brain's attempt to make sense of random neural static. (BRAIN NOISE)

    
    

58. 
    

    Consolidation Theory: Sleep helps transfer info into long-term memory. (MEMORY FILING)

    
    

59. 
    

    Sensory Transduction: Converting physical energy (light/sound) into neural impulses. (CONVERSION)

    
    

60. 
    

    Absolute Threshold: Minimum stimulus needed to detect it 50% of the time. (DETECTION)

    
    

61. 
    

    Just-noticeable Difference (JND): Minimum difference between two stimuli to detect change. (DIFFERENCE)

    
    

62. 
    

    Weber’s Law: Two stimuli must differ by a constant percentage to be perceived as different. (PROPORTION)

    
    

63. 
    

    Sensory Adaptation: Diminished sensitivity to a constant stimulus (e.g., a smell goes away). (GETTING USED TO IT)

    
    

64. 
    

    Retina: Light-sensitive inner surface of the eye. (VISUAL SCREEN)

    
    

65. 
    

    Rods: Detect black, white, and gray; used for night vision. (NIGHT VISION)

    
    

66. 
    

    Cones: Detect fine detail and color; used in daylight. (COLOR/DETAIL)

    
    

67. 
    

    Fovea: Central point in the retina where cones cluster; sharpest vision. (SHARPEST VISION)

    
    

68. 
    

    Trichromatic Theory: The retina has three color receptors (Red, Green, Blue). (RGB)

    
    

69. 
    

    Opponent-Process Theory: Color is processed in opposing pairs (Red-Green, Blue-Yellow); explains afterimages. (AFTERIMAGES)

    
    

70. 
    

    Place Theory: We hear pitch based on where the cochlea is stimulated. (LOCATION PITCH)

    
    

71. 
    

    Frequency Theory: We hear pitch based on the rate of neural impulses. (MATCHING RATE)

    
    

72. 
    

    Sensorineural Deafness: Hearing loss from damage to the cochlea or auditory nerve. (NERVE DAMAGE)

    
    

73. 
    

    Conduction Deafness: Hearing loss from damage to the ear's mechanical system. (MECHANICAL DAMAGE)

    
    

74. 
    

    Gate Control Theory: The spinal cord blocks or allows pain signals to reach the brain. (PAIN GATE)

    
    

75. 
    

    Vestibular Sense: Monitors body position and balance (controlled by inner ear). (BALANCE)

    
    

76. 
    

    Kinesthesis: Sensing the position and movement of individual body parts. (PART POSITION)