Nervous System in Animals

• The Nervous System is the body's command center, composed of the brain, spinal cord, and nerves
• It sends messages or electrical signals from the brain to all parts of the body
• These signals help organisms to do work such as breathing, moving, speaking, and seeing
• The Nervous System regulates processes like thinking, remembering, and decision making
• Central Nervous System (CNS) comprises the brain and spinal cord
• Located in the head and continues along the back
• Responsible for processing information and sending it out to the body
• Peripheral Nervous System includes all nerves continuing from the CNS to the entire body
• Relays signals from the CNS to the periphery by motor nerves
• Divided into Autonomic and Somatic Nervous Systems
• Autonomic Nervous System regulates involuntary processes like heart rate and digestion
• Has two divisions: Sympathetic (fight-or-flight) and Parasympathetic (rest and digest)
• Somatic Nervous System regulates voluntary processes like muscle control and movement
• Consists of nerve fibers that control voluntary actions and convey sensory information
• Simple invertebrates have a rudimentary nervous system allowing them to sense and respond to external stimuli
• Nervous system lacks complexity and is decentralized
• Primarily distributed throughout the body as a diffuse network of neurons known as a nerve net
• Complex invertebrates develop more complicated neural systems to support sophisticated behaviors and sensory processing
• Made up of ganglia and brain, which integrates sensory input and coordinates motor responses
• Nerve cords link the brain and ganglia to peripheral nerves and sensory organs
• Fish brains have a lot of cerebellum for muscle movement modulation and balance preservation
• Amphibians have a midbrain responsible for vision processes
• Reptiles have olfactory bulb for smell regulation and limbic system for mood and behavior
• Birds have a large cerebellum for flying coordination and enhanced optic lobes for visual information assimilation
• Neurons are responsible for sending impulses between central and peripheral neural systems
• Three categories: interneurons, motor neurons, and sensory neurons
• Nerves and ganglia carry impulses from the CNS to organs in the peripheral nervous system
• Nerves transmit electrochemical impulses and coordinate bodily functions
• Ganglia are oval-shaped and maintain the connection between central and peripheral neural systems
• The brain interprets sensory data, initiates motor reactions, and controls bodily processes
• Made up of diencephalon, brain stem, cerebellum, and cerebrum
• Spinal cord connects the brain to the lower back and conveys motor and sensory information
• Sensory input involves activating sensory receptors and translating events into electrical signals
• Perception results from filtering, processing, and interpreting signals in the brain
• Nervous system integrates and processes information through transmission of impulses between neurons
• Cognitive processing, production of motor output, and reception of feedback enable perception, judgment, and behavioral reactions
• Nervous system coordinates and regulates motor output through a network of neurons
• Motor cortex communicates with muscles to plan and carry out voluntary actions
• Basal ganglia and cerebellum aid in controlling and fine-tuning movement
• Brain detects movement faults through sensory feedback from receptors to enable corrections