How much of your brain do you use each day?

- - The movie Lucy is not true at all - ooWe use virtually all of the brain - ooMost of the brain is being used at all times

How does the brain communicate with the body?

  • PNS peripheral nervous system
    • ooTwo primary components
      • Somatic
        • Transmits signals from cns
      • Autonomic nervous system
        • Regulates body’s internal environment

Autonomic nervous system

  • Sympathetic
    • ooPrepares fight or flight
  • Parasympathetic division

    • ooReturns body to normal

The Endocrine system

  • Endocrine system
    • ooCommunication network influences thoughts, behaviors, and actions

Hormones & Sexual Behavior

  • Gonads
    • ooEndocrine glands influencing sexual behavior
  • Gonadal hormones are identical in males and females
    • ooAndrogens (testosterone) is simply more prevalent in males (women have them to some degree)
    • ooEstrogens
      • Men have it too, but not as much

The Nervous System & the Endocrine System

  • Under the CNS’s control

The four f’s

  • Fighting
  • Fleeing
  • Fleeting
  • Reproduction…

  • Phineas Gauge stabbed during work straight through the brain and lived, but altered personality-wise forever.

The Brain can Recover from Injury

  • Radical hemispherectomy
    • ooSurgery to remove half the brain

The Interplay of Genes and Environment Wires the Brain

  • Nature and nurture constantly interact to affect DNA’s activity and the products of that activity
    • ooBrain adapts on biological level
      • Learning
      • Skills that are gained over time actually change the brain
        • If you couldn’t play an instrument and now you can, you changed your brain
  • Tissue transplanted early enough completely transforms into whatever type appropriate for new location

Experience Fine-Tunes Neural Connections

  • Experience is important for normal brain development and maybe more so for superior developments
    • ooExample
      • Genie
        • Can’t speak because she missed a critical time in her childhood to learn to speak
        • People try to teach languages to children because children have more brain placticity
      • Mice
        • One mouse was placed in a cage with basic stuff available
        • Other mouse was placed in a cage with ladders and obstacles and stuff and these mice had bigger brains at the end of their lives
          • This is true with humans as well
            • Cab drivers in London have to memorize a lot of streets and have growing brains

Culture Affects the Brain

  • Our cultural experiences contribute to different patterns of brain activity
    • ooWhen people see people expressing emotions, they have more of a empathetic response when those people are from their culture

Brain Rewires Itself

  • Although brain plasticity decreases with age, brain can grow new connections among neurons into very old age
    • ooIf you start learning to play piano when you’re ten, it’s easier to learn than if you’re 40

Change in the Strength of Connections Underlies Learning

  • Changes in brain due to experience
  • Entirely new connections can grow between neurons
  • Neurogenesis may underlie neural plasticity

Vocab

Somatic nervous system Transmits sensory signals to and from the central nervous system
Autonomic nervous system Regulates the body’s internal environment (carries signals from the glands and internal organs to the central nervous system)
Sympathetic division Prepares the body for action (Part of ANS)
Parasympathetic division Returns the body to its normal, resting state (Part of ANS)
Endocrine system Communication network influences thoughts, behaviors, and actions
Hormones Chemical substances released into the bloodstream by the endocrine glands (such as the pancreas, thyroid, and testes or ovaries)
Pituitary gland Governs the release of hormones from the rest of the endocrine glands responsible for major bodily process
Radical hemispherectomy Surgical removal of entire cerebral hemisphere
Neurogenesis New neurons are produced in some brain regions (hippocampus)