Insect Nervous
System
Department of
Pest
Management
College of
Agriculture and
Food Science
Structure of the Nervous System
• The central nervous system
• insect CNS consists of the brain
and ventral nerve cord
Department of
Pest
Management
College of
Agriculture and
Food Science
• Protocerebrum
• connects to the eyes
• allows the insect to detect light,
movement and also see
• Deutocerebrum
• Connects to the antennae
• Used to collect information on tastes,
smells, temperature, humidity and
other sensations
• Tritocerebrum
• Connects the upper tip of the insect’s
mouth and process information from
other lobes
Structure of the Nervous System
• The central nervous
system
Department of
Pest
Management
College of
Agriculture and
Food Science
• Ganglia- nerve centers
consisting of cell bodies
of interneurons and motor
neurons aggregated with
fibers interconnecting all
types of nerve cells
Neuron
• Nerve cells, or neurons, are the cellular building
blocks that make up the nervous system
• capable of integrating information
• undergoing excitation
• transmitting the information by electrical and short-range
chemical signaling (action potential)
Department of
Pest
Management
College of
Agriculture and
Food Science
• The chemical signaling occurs via the synapses that
connect with other neurons to form more complex
neural networks.
• Dendrites bring information to the soma
• Axons take information away from the soma.
Neurons are usually divided into three categories, depending on the
direction of information
• Afferent (sensory) neurons — these bipolar or multipolar cells have
dendrites that are associated with sense organs or receptors. They
always carry information toward the central nervous system.
• Efferent (motor) neurons — unipolar cells that conduct signals away
from the central nervous system and stimulate responses in muscles
and glands.
• Internuncial (association) neurons — unipolar cells (often with several
collaterals and/or branching axons) that conduct signals within the
central nervous system.
Department of
Pest
Management
College of
Agriculture and
Food Science