PSYC301
Lecture 1- 9/9
Neuroscience → study of the nervous system (50s-60s)
- Developments
- Surgical recordings from the human cortex (Penfield)
- Study of the action potential (Hodgkin& Huxley)
- Learning in the synapse (Kandel)
Behavioural neuroscience → study of the nervous system as it relates to behaviour
Cognitive neuroscience → study of how cognitive processes occur in the brain
- through the lens of academic research
Neuropsychology → the study of the brain in functional and dysfunctional states
- Injuries and their outcome
- More medicine/clinical lens
,Revision
Cells of the Nervous System
the nervous system is made up of specialized cells, including nerve cells (or neurons)
and glial cells (or glia).
- Neurons are the basic functional units of the nervous system, and they generate
electrical signals called action potentials, which allow them to quickly transmit
information over long distances.
- Glia are also essential to nervous system function, but they work mostly by
supporting the neurons.
Anatomy of Neurons
cell body (also called the soma).
- The nucleus of the neuron is found in the soma.
- contains all of the structures (or organelles) that are needed to keep the neuron
alive and functioning
processes: protrusions or branches that stick out from the cell body
- many short, branching processes called dendrites.
o Dendrites are responsible for receiving and processing incoming information.
o Incoming signals can be either excitatory, which means they tend to make
the neuron fire (generate an electrical impulse)
o or inhibitory, which means that they tend to prevent the neuron from firing.
o A single neuron may have more than one set of dendrites and may receive
many thousands of input signals from other neurons.
o Whether or not a neuron is excited into firing depends on the sum of all of the
excitatory and inhibitory signals it receives.
o If the neuron does end up firing, the nerve impulse, or action potential, is
conducted down the axon.
- axon which are typically much longer than the dendrites
o The axon arises from the cell body at a specialized area called the axon
hillock.
o Many axons are covered with a special insulating substance called myelin,
which helps them convey the nerve impulse rapidly. Myelin is never found on
dendrites.
,o Towards its end, the axon splits up into many branches and develops
bulbous swellings known as axon terminals (or nerve terminals). These
axon terminals make connections on target cells. In other words, while
dendrites typically receive input from other neurons, axons typically work to
send outputs to other neurons.
, Lecture 2- 11/9
NS -> CNS (central nervous system) + PNS (peripheral nervous system)
CNS -> Brain + Spinal cord
Somatic NS interacts with the external environment
- has afferent nerves that carry sensory signals in from
SNS
the skin, skeletal muscles, joints, eyes etc into the CNS
o impulse moving proximally
- has efferent nerves that carry motor signals from the
PNS
CNS out to skeletal muscles (efferent exits the CNS)
Autonomic NS deals with regulation of the internal
ANS environment
- has afferent nerves that carry sensory signals from the
internal organs to the CNS
- has efferent nerves that carry motor signals from the
CNS out to internal organs
Sympathetic Nervous syetem
- Autonomic motor nerves projecting from the
CNS in the lumbar and thoracic regions of
Parasympathetic Nervous syetem
the spinal cord
- Mobilizes energy resources in threatening - Autonomic motor nerves projecting
situations from the brain and sacral region of
- physiological arousal, EG via adrenal glands the spinal cord
o Increased heart rate - Conserves energy
o Decreased digestion - physiological relaxation
o constricts arteries found within the o Constricting pupils
salivary glands. o Slowing heart rate
- synapse on second-stage neurons at a - synapse near their target organs on
substantial distance (distal) from their target very short (proximal) second-stage
organs neurons
- two-stage neural paths: neurons project from the CNS and go only part of the way to the target
organs before they synapse on other neurons (second-stage neurons) that carry the signals the rest
of the way
- each autonomic target organ receives opposing sympathetic and parasympathetic input, and its
activity is thus controlled by relative levels of sympathetic and parasympathetic activity
Lecture 1- 9/9
Neuroscience → study of the nervous system (50s-60s)
- Developments
- Surgical recordings from the human cortex (Penfield)
- Study of the action potential (Hodgkin& Huxley)
- Learning in the synapse (Kandel)
Behavioural neuroscience → study of the nervous system as it relates to behaviour
Cognitive neuroscience → study of how cognitive processes occur in the brain
- through the lens of academic research
Neuropsychology → the study of the brain in functional and dysfunctional states
- Injuries and their outcome
- More medicine/clinical lens
,Revision
Cells of the Nervous System
the nervous system is made up of specialized cells, including nerve cells (or neurons)
and glial cells (or glia).
- Neurons are the basic functional units of the nervous system, and they generate
electrical signals called action potentials, which allow them to quickly transmit
information over long distances.
- Glia are also essential to nervous system function, but they work mostly by
supporting the neurons.
Anatomy of Neurons
cell body (also called the soma).
- The nucleus of the neuron is found in the soma.
- contains all of the structures (or organelles) that are needed to keep the neuron
alive and functioning
processes: protrusions or branches that stick out from the cell body
- many short, branching processes called dendrites.
o Dendrites are responsible for receiving and processing incoming information.
o Incoming signals can be either excitatory, which means they tend to make
the neuron fire (generate an electrical impulse)
o or inhibitory, which means that they tend to prevent the neuron from firing.
o A single neuron may have more than one set of dendrites and may receive
many thousands of input signals from other neurons.
o Whether or not a neuron is excited into firing depends on the sum of all of the
excitatory and inhibitory signals it receives.
o If the neuron does end up firing, the nerve impulse, or action potential, is
conducted down the axon.
- axon which are typically much longer than the dendrites
o The axon arises from the cell body at a specialized area called the axon
hillock.
o Many axons are covered with a special insulating substance called myelin,
which helps them convey the nerve impulse rapidly. Myelin is never found on
dendrites.
,o Towards its end, the axon splits up into many branches and develops
bulbous swellings known as axon terminals (or nerve terminals). These
axon terminals make connections on target cells. In other words, while
dendrites typically receive input from other neurons, axons typically work to
send outputs to other neurons.
, Lecture 2- 11/9
NS -> CNS (central nervous system) + PNS (peripheral nervous system)
CNS -> Brain + Spinal cord
Somatic NS interacts with the external environment
- has afferent nerves that carry sensory signals in from
SNS
the skin, skeletal muscles, joints, eyes etc into the CNS
o impulse moving proximally
- has efferent nerves that carry motor signals from the
PNS
CNS out to skeletal muscles (efferent exits the CNS)
Autonomic NS deals with regulation of the internal
ANS environment
- has afferent nerves that carry sensory signals from the
internal organs to the CNS
- has efferent nerves that carry motor signals from the
CNS out to internal organs
Sympathetic Nervous syetem
- Autonomic motor nerves projecting from the
CNS in the lumbar and thoracic regions of
Parasympathetic Nervous syetem
the spinal cord
- Mobilizes energy resources in threatening - Autonomic motor nerves projecting
situations from the brain and sacral region of
- physiological arousal, EG via adrenal glands the spinal cord
o Increased heart rate - Conserves energy
o Decreased digestion - physiological relaxation
o constricts arteries found within the o Constricting pupils
salivary glands. o Slowing heart rate
- synapse on second-stage neurons at a - synapse near their target organs on
substantial distance (distal) from their target very short (proximal) second-stage
organs neurons
- two-stage neural paths: neurons project from the CNS and go only part of the way to the target
organs before they synapse on other neurons (second-stage neurons) that carry the signals the rest
of the way
- each autonomic target organ receives opposing sympathetic and parasympathetic input, and its
activity is thus controlled by relative levels of sympathetic and parasympathetic activity
