NEUR 2600 Lecture Notes - Lecture 2: Cerebral Circulation, Midbrain Tectum, Afferent Nerve Fiber
CHAPTER 2: WHAT IS THE NERVOUS SYSTEM’S FUNCTIONAL ANATOMY
Overview of brain function and structure
●Evolution of brain size and human behaviour
○The human brain has optimal overall size (size and number of neurons, number
and length of connections, energy consumption)
○Changing these features would compromise others and neutralize any
improvements in performance
○PRINCIPLE 1:
■The brain’s primary function is to produce behaviour (movement)
■To do so it must,
●Receive information about the world
●Integrate information to construct a subjective experience of reality
(perception)
●Produce commands to control the movement of muscles
○PRINCIPLE 2: PLASTICITY
■The brain is plastic
●Neural tissue has the capacity to adapt to the world by changing
how its functions are organized
■Neuroplasticity
●The nervous system’s potential for physical or chemical change
that enhances its adaptability to environmental change and its
ability to compensate for injury
●An individual’s genotype (genetic makeup) interacts with the
environment to elicit a specific phenotype from a large genetic
repertoire of possibilities, a phenomenon that results from
epigenetic influences
●Functional Organization of nervous system (Recall)
○Brain and spinal cord make up the CNS. The nerve fibers radiating from the CNS
and the neurons outside it constitute the PNS
○Anatomical divisions
■
■PNS nerves carry sensory information to the CNS and carry motor
instructions from it to the muscles and tissues, including those responsible
for such functions as blood circulation and digestion
○Functional divisions
■
■The CNS and the PNS constitute an interacting four-part system
●The CNS consists of the brain and spinal cord
●The somatic nervous system (SNS) consists of spinal and cranial
nerves that carry sensory information to the CNS from the
muscles, joints and skin. It also transmits outgoing motor
instructions that produce movement
●The autonomic nervous system (ANS) prepares internal organs for
the “rest-and-digest” response via the parasympathetic (calming)
nerves or the flight-or-fight response through the sympathetic
(arousing) nerves
●The enteric nervous system (ENS), formed by a mesh of neurons
embedded in the lining of the gut, controls the gut. The ENS
communicates with the CNS via the ANS but mostly operates
autonomously
■Direction of neural information
●Afferent
information is sensory information coming into the CNS
(incoming information)
●Efferent
information is information leaving the CNS (outgoing
information)
●Brain-Body Orientation
○
●Spatial Orientation
Document Summary
Chapter 2: what is the nervous system"s functional anatomy. Evolution of brain size and human behaviour. The human brain has optimal overall size (size and number of neurons, number and length of connections, energy consumption) Changing these features would compromise others and neutralize any improvements in performance. The brain"s primary function is to produce behaviour (movement) Integrate information to construct a subjective experience of reality (perception) Produce commands to control the movement of muscles. Neural tissue has the capacity to adapt to the world by changing how its functions are organized. The nervous system"s potential for physical or chemical change that enhances its adaptability to environmental change and its ability to compensate for injury. An individual"s genotype (genetic makeup) interacts with the environment to elicit a specific phenotype from a large genetic repertoire of possibilities, a phenomenon that results from epigenetic influences. Brain and spinal cord make up the cns.
