THE BRAIN AND THE SPINAL CORD

The Human Brain

FUNCTIONS OF THE BRAIN

IT RECEIVES MESSAGES FROM AND SENDS MESSAGES TO ALL ORGANS AND TISSUES OF THE BODY

IT CONTROLS BOTH VOLUNTARY & INVOLUNTARY ACTIVITIES

THE BRAIN GIVES US THE ABILITY TO LEARN, TO REASON AND TO FEEL

3 MAIN PARTS:

1. BRAIN STEM2. CEREBELLUM3. CEREBRUM

1. BRAIN STEM

THE LOWEST SECTION OF THE BRAIN WHICH CONNECTS IT TO THE SPINAL CORD

IT HAS 3 PARTS: Medulla Pons Midbrain

2. CEREBELLUM

IS AT THE BACK OF THE BRAIN STEM AND IS LINKED TO IT BY NERVE TRACTS

IT IS CONCERNED WITH THE MAINTENANCE OF POSTURE AND BALANCE, AND THE COORDINATION OF MOVEMENTS

3. CEREBRUM

LARGEST PART OF THE BRAIN

HAS 2 HEMISPHERES SEPARATED BY A GROOVE

IS DIVIDED INTO 4 SECTIONS OR LOBES

THALAMUS – CONSISTS OF TWO EGG-SHAPED MASSES OF NERVE TISSUE WHICH RECEIVE MESSAGES FROM THE SENSORY NEURONS AND SEND THEM TO SPECIFIC AREAS IN THE CEREBRUM WHERE THEY ARE INTERPRETED.

HYPOTHALAMUS – LIES BETWEEN THE THALAMUS AND THE PITUITARY GLAND

Frontal lobe—conscious thought; damage can result in mood changesParietal lobe—plays important roles in integrating sensory information from various senses, and in the manipulation of objects; portions of the parietal lobe are involved with visuospatial processingOccipital lobe—sense of sight; lesions can produce hallucinationsTemporal lobe—senses of smell and sound, as well as processing of complex stimuli like faces and scenes.

Brain in the flesh

THE SPINAL CORD

Is a part of the CENTRAL NERVOUS SYSTEM.

Begins at the base of the skull and extends throughout most of the backbone, or vertebral column

Structure

MAIN FUNCTIONS

IT IS THE LINK BETWEEN THE PERIPHERAL NERVOUS SYSTEM (PNS) AND THE BRAIN.

HANDLES SOME INFORMATION COMING FROM THE SENSES AND PROVIDE MOTOR RESPONSES THAT DO NOT COME FROM THE BRAIN. THIS IS CALLED A REFLEX ACTION.