BIOPSYCHOLOGY - The Nervous System Flashcards
(16 cards)
Nervous system (holistic definition)
A specialised network of nerve cells in the human body and is our primary internal communication system
Two main functions of the nervous system
To collect, process and respond to information in the environment
To coordinate the working of different organs and cells in the body
Two subsystems of the nervous system
Central Nervous System
Peripheral Nervous System
What makes up the Central Nervous System?
Brain & spinal cord
Describe the brain in the Central Nervous System
• Centre of all conscious awareness
• Outer layer is the cerebral cortex which is highly developed in humans which distinguishes our higher mental functions than that of animals
• Divided into two hemispheres; left and right
• Four divisions of the brain are cerebrum, cerebellum, diencephalon and the brain stem
Describe the spinal cord in the Central Nervous System
• To relay information between the brain and the rest of the body
• This allows the brain to monitor and regulate bodily processes like digestion and breathing
• Spinal cord is connected to different parts of the body by pairs of spinal nerves which connect the specific muscles and glands
• Also contains circuits of nerve cells that enable us to perform simple reflexes without the direct involvement of the brain
Function of the Peripheral Nervous System
Transmit messages to and from the Central Nervous System via nerve cells
Subdivisions of the Peripheral Nervous System
Somatic Nervous System
Autonomic Nervous System
Describe the cerebrum as part of the brain
• Largest part of the brain
• Made up of the frontal lobe, temporal lobe, parietal lobe and occipital lobe
• Split into halves called cerebral hemispheres which communicate via the corpus callosum
Describe the cerebellum as part of the brain
• Sits at the back of the cerebrum
• Involved in controlling a person’s motor skills and balance to coordinate precise movement
Describe the diencephalon as part of the brain
• Central location within the brain sitting just about the brain stem
• Divided into the thalamus, hypothalamus, epithalamus and subthalamus
• Involved in coordinating with the endocrine system to release hormones, relaying sensory and motor signals to and from the cerebral cortex and regulating circadian rhythms
Describe the brain stem as part of the brain
• Responsible for regulating automatic functions such as breathing and the heartbeat
• Motor and sensory neurons travel through the brain stem to allow impulses to travel between the spinal cord and brain stem
Describe the Somatic Nervous System as part of the Peripheral Nervous System
• Made up of 12 pairs of cranial nerves and 31 pairs of spinal nerves which have both sensory and motor neurons
• Involved in reflex actions without the involvement of the CNS which allows the reflex to happen very quickly
• SNS control centre is in the motor cortex part of the brain
• Used to carry sensory information from the outside world to the brain and provide muscle responses via the motor pathways
Describe the Autonomic Nervous System as part of the Peripheral Nervous System
• Regulates involuntary actions such as heartbeats so is responsible for regulating automatic internal bodily responses aka homeostasis
• Made up of only motor nerve pathways
• ANS control centre is in the brain stem
• Made up of two parts; sympathetic and parasympathetic nervous systems
• Both parts regulate the same organs but have the opposite effects
• Sympathetic uses noradrenaline which is stimulating
• Parasympathetic uses acetylcholine which is inhibiting
Describe the Sympathetic Nervous System as part of the Autonomic Nervous System
• Involved in emergency responses such as fight or flight by increasing heart rate, blood pressure and vasodilation
• Neurons from the sympathetic nervous system travel to almost every organ and gland in the body preparing it for rapid action
• For example can cause the body to increase heart rate, blood pressure and breathing rate and suppress functions like digestion and desire to urinate
Describe the Parasympathetic Nervous System as part of the Autonomic Nervous System
• Parasympathetic nervous system relaxes an individual after an emergency has passed
• For example slows the heartbeat down and reduces blood pressure and restarts digestion
• Returns the body to its normal resting state
