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📋 Summary

Development of the Nervous System-VII 🎨✨

PSYP610 - Neurological Bases of Behavior

Stimulation is EVERYTHING! 📡💪

👁️ Hubel & Wiesel's Classic Experiments (1963)

  • Closed one eye in newborn kitten 🐱👁️✂️
  • Result: Monocular response only! 👁️❌
  • Visual system intact, but can't process! ✅⚠️

🕶️ Dark Room Kittens

  • Kept in darkness from birth 🌑
  • Visual pathways atrophy! 👁️💀
  • Visual cortex degenerates! 🧠⬇️
  • PERMANENT BLINDNESS! 🙈❌

🎨 Enriched Environment Studies

🐀 Rosenzweig's Rats (1969, 1972)

Rats raised with toys, swings, ladders! 🧸🎠🪜

Results:

  • ⬆️ Increased brain weight! 🧠⚖️
  • ⬆️ Thicker cortical tissue! 📏
  • ⬆️ Larger neurons! 🧫
  • ⬆️ More glial cells! 🔬
  • ⬆️ More dendritic spines! 🌿
  • 🧪 Different brain chemistry! ⚗️

🌿 Greenough's Findings (1975)

  • Increased dendritic sprouting! 🌱📈
  • Responded better to novelty! 🌍✨
  • Like mildly stressed rats (good stress)! 😰✅

⏰ Critical Periods Matter!

  • Timing is EVERYTHING! ⏰✅
  • Stimulation needed at RIGHT time! 📡🎯
  • Too early = No effect! ⏪❌
  • Too late = No repair possible! ⏩❌
  • Window of opportunity! 🪟✨

💨 Oxygen: Can't Live Without It!

  • Critical during growth! 🌱💨
  • Mother's oxygen = Baby's oxygen! 🤰💨
  • Hypoxia = Brain damage! 💨⚠️
  • Anemia/heart problems in mother = Problems! 🩸💔⚠️
  • Neurons die without oxygen! 💀

💪 Motor Activity in Uterus

  • Movement = Stronger muscles! 🤰🏃💪
  • Exercises connections! 🔗
  • Sensory responses too! 👂👁️
  • Fetus responds to lullabies! 🎵👶
  • Stimulated fetuses more alert at birth! 👀🍼

💊 Teratogenic Effects

  • Thalidomide: 1960s sedative = Major deformities! 😴💊🦾⚠️
  • Avoid: Morphine 💉, Heroin 💉, Alcohol 🍷, Nicotine 🚬, Cocaine 💊, Tobacco 🚬
  • Placental barrier not enough! 🛡️❌
  • 1st three months MOST critical! 📅⚠️

📡 Sensory Deprivation = Disaster!

  • No stimulation = No development! 📡❌💪
  • Organs/muscles need input! 🔌
  • Irreversible defects! ❌💔
  • Now babies get mobiles & colorful toys! 🎨🧸

🔑 Key Takeaways

  • Stimulation = Growth! 📡📈
  • Deprivation = Degeneration! ⬇️💀
  • Enriched environment = Bigger brain! 🎨🧠⬆️
  • Critical periods are windows! ⏰🪟
  • Can't repair after window closes! ❌
  • Oxygen is non-negotiable! 💨✅
  • Drugs destroy developing brains! 💊☠️
  • Environment extremely important! 🌍⚡