Exam 1: Neuro and Development

NAVIGATION IN THE BRAIN

DORSAL-SUPERIOR
VENTRAL-INFERIOR
ANTERIOR-ROSTRAL
POSTERIOR-CAUDAL

CEREBRAL CORTEX

HAS TWO HEMISPHERES DIVIDE BY THE LONGITUDINAL FISSURE
-NEURONS ARE ARRANGED IN LAYERS ABOUT 3 MM THICK

GYRI

separated by sulci and result from the folding of the cerebral cortex that occurs during development of the nervous system, to achieve an economy of size.

SULCI

THREE TYPES:
-PRIMARY: SEPARATE MAJOR LOBES
-SECONDARY: INCREASE VARIATION
-TERTIARY: HAS MOST INDIVIDUAL VARIATION

GRAY MATTER

COMPOSED PRIMARILY OF NEURONS (OUTSIDE LINING OF THE BRAIN)

WHITE MATTER

is composed of myelinated axons, that transmit signals, (inside portion of the brain)

DENDRITES

RECEIVE SIGNALS FRIM AXONS

AXON

TRANSMITS SIGNALS TO DENDRITE

CENTRAL SULCUS

DIVIDS FRONTAL AND PARIETAL LOBE

FOUR CEREBRAL LOBES

FRONTAL
PARIETAL
TEMPORAL
OCCIPITAL

NATURE VS. NURTURE

GENETICS VS. EXPERIENCE

RENE SPITZ'S RESEARCH

1940'S, BABIES WERE RAISED IN A FONDLING HOME OTHERS WERE RAISED BY PRISON INMATE MOTHERS. THOS RAISED BY INMATES TURNED OUT NORMAL COMPARED TO THOSE IN FONDLING HOME WHO WERE MORE WITHDRAWN
-BABIES ARE NOT BLANK SLATES AND GENES SHAPE THEIR CAPABILITY TO LEARN

NEURAL DEVELOPMENT

17 days- neural plate begins to develop
19 days- neuralation begins after fertilization (formation of the central nervous system)
25 days- neural plate folds up to form a groove
26 days- tube running the length of the embryo is closed
-finishes first in the head then in the tail (becomes spinal cord)
-divides into three parts, forebrain, midbrain and hindbrain
- then the telencephalon (forms the left and right hemispheres) and the diencephalon form
8 weeks- fetus status is achieved
13 weeks- thalamus and cerebellum are formed
24 weeks- can breathe air and can be controlled by the brain stem

TELENCEPHALON

forms left and right hemispheres, then develops into the Pons, medulla, cerebellum, thalamus, basal ganglia, limbic system and cerebral cortex

diencephalons, mesencehpalon,
metenencephalon, & myencephalon

PARTS THAT SHOW THEMSELVES DURING NEURALATION

NEUROGENESIS

THE GROWTH AND BIRTH OF NEURONS

NUMBER OF SYNAPSES

• more synapse equals more plasticity
• critical period is marked by significant reduction in synapses

MYELINATION

• development and function of myelination
o fatty layer of insulation that cover axons
o 80% lipid and 20% protein
o prevents interference from tightly packed fibers, and enhances the speed of conduction by preventing the leaking of charged ions through pores in the membrane
o axons cannot transmit with myelin
o deficient in myelin suffer from MS
o begins in early gestation for the spinal cord, becomes thickened throughout