Chapter 8

The Brain in Control of It All

Evolution of the Brain

The Primitive Brain Still Resides in the Human Brain

The Brain

• Controls all functions of the body

• The purpose is to protect the brain’s environment

• The brain selects its own environment from the general water environment of the body, the blood

• The brain collects information and adjusts the body

Information

The Nerve Cell

Transmitting A Signal

Signaling

Neurotransmitters

• Many different neurotransmitters

• Some depolarize, make the inside/outside less different (facilitate passing on signals)

• Some hyperpolarize, make the inside/outside more different (inhibit passing on signals)

• Some go both ways (depending on the receiving cell)

Nerve Cell

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In general each nerve cell both receives signals from many other nerve cells and sends signals to many other nerve cells

Spinal cord

Excitation and Inhibition Work Together

Autonomic Nervous system

Parasympathetic

Parasympathetic

Sympathetic

CALM Excited/danger

MedullaAutonomic nervous system, breathing etc

Hypothalmus and pituitary gland

Pituitary Gland

Balance: Negative Feedback

Limbic System

Reticular Activating System

The basic core of the brain

Cerebellum: motor guidance

Cerebellum

Cerebral Cortex

Localized Functions

Two Brains

Drugs

• Information or disinformation

• Alter balance

• Tolerance

• Dependence