THE NEURON

Chapter 2: Biological Basis of Human Behavior

John Hermes C. UntalanInstructor, General Psychology 1st Sem 08-09

De La Salle Araneta University

Objectives

Describe the nature of the basic structural unit of the nervous system in terms of its parts, types, functions, and other properties

Explain how sensory and motor signals are conducted to and from the brain Discuss the divisions of the nervous system and the structures that form each division Point out the specialized functions of each cerebral hemispheres Enumerate the different neurotransmitter substances and their effects on behavior Enumerate the different endocrine glands and explain the role played by the endocrine system in controlling behavior Discuss the influences of hereditary units on behavior

Neurogenesis

development of the nervous system, during this time: neurons are generated from undifferentiated stem

cells; the neurons migrate from the site where they were

generated to their final positions; the neurons aggregate into distinct brain regions;

and neurons begin to make connections among one

another

Three Different Types of Neurons

Sensory (Afferent) NeuronsCarry messages from the body’s sense receptors to the

CNS.Motor (Efferent) Neurons

Carry signals from the CNS to the muscles and glands.

InterneuronsForm all the neural wiring within the CNS which has

two axons. One axon communicate with the spinal cord while the other with the skin or muscle.

The Human Nervous System

Central Nervous System

BrainCerebrum (Telen.)Cerebellum (Meten.-Dorsal)

Brain StemMedulla (Myelen.)Pons (Meten.-Ventral)Midbrain (Mesen.)Interbrain (Dien.)

Spinal CordCervical (8 pairs)Thoracic (12 pairs)

Lumbar (5 pairs)Sacral (5 pairs)Coccygeal (1 pair)

Peripheral Nervous System

Somatic Nervous SystemSpinal Nerves (31 pairs)Cranial Nerves (12 pairs)

Autonomic Nervous SystemSympathetic (excite)Parasympathetic (inhibit)