Psychology Exam 2 notes:
The biological bases of behaviour
- Studying psychology without a solid understanding on the brain’s
biology is challenging
Ideas, moods, feelings, etc. are biological phenomena
Localization of Function:
- Psychologists have moved away from phrenology to a more modern
understanding of localization (one part of the brain does this compared
to another)
While Franz Joseph Gall’s notion of phrenology was incorrect, the
concept of phrenology is important.
Biology, behaviour and mind:
- A critical analysis of what parts of the brain are responsible for certain
actions is a cogent endeavour
When we work from a biological POV, we can study links between
biological activity in the brain and psychological events
- Humans are biopsychosocial systems
Cells organize to form our organs and these organs from larger
systems for digestion, circulation, etc.
These systems form a larger system, an individual human being
who perceives the world uniquely.
Who is, in turn, part of a family, community, and culture
,Neural communication:
- Neurons: individual cells that receive, integrate, and translate
information
Communication between body and brain occurs via neurons
Different types of neurons in our bodies exist but all are
variations on the same general theme
Each type consists of a cell body and fibers:
Cell body (contains nucleus and acts like a tiny
factory for proteins and neurotransmitters)
Dendrites (look like branches, gather information
from other cells)
Axons (may have multiple terminals or just one,
transmits signals from soma to other neurons)
Branch-like dendrites receive electrical impulses from other
neurons and conduct them toward the cell body or “soma”
From there, a neuron’s axon transfers info through its terminals
to other neurons, or to muscles/glands in the body
Axons can be long, so dendrites “listen” and axons
“speak”.
- Like how electrical wires at home are insulated, so are some axons
when encased in a myelin sheath.
, Sheath is a layer of fatty material that insulates some axons
Regular spaces exist where stealth becomes thin or
nonexistent, these are called nodes of Ranvier
As myelin is laid onto different neurons until around 25 y/o which
is when neural efficiency and self-control grows.
Degeneration of myelin is part of the disease called
multiple sclerosis
Multiple sclerosis causes the immune system to
malfunction and attack glial cells that insulate
neurons in brain and spinal cord
Causes fatigue, vision problems, and movement
issues (speech difficulties, paralysis)
- Billions of glial cells support this process.
Glial cells provide nutrients and oxygen to neurons, as well as to
myelin
These stabilize neurons and destroy dead neurons and
pathogens because they are phagocytes (eat other cells)
In complex brains (dolphins, crows, people) the ratio of glia
to neurons is high when compared to less complex brains.
Depending on the location, different glial cell types make myelin.
, Schwann cells make myelin in the peripheral nervous
system (PNS) while oligodendrocyte do this in the central
system (CNS)
- Glial cells provide protection to the brain in three ways;
They produce cerebrospinal fluid, a colourless fluid surrounding
the brain and spinal cord
They form the blood brain barrier, which prevents foreign
material like some viruses and drugs from entering the brain
They contribute to the brain’s immune system.
While several molecular and morphological differences
exist between neurons in the PNS and CNS, the basic
myelin sheath arrangements are essentially the same
- A = Cell Body, B = Glial Cell, C = Axon
The Neural Impulse in General:
- Neurons transmit messages when they are stimulated by signals from
senses,
or when triggered by chemical signals from neighbouring
neurons.
- In response to stimulation, a neuron fires an electrical impulse called
an action potential
This is a brief electrical change that travels along an axon
The biological bases of behaviour
- Studying psychology without a solid understanding on the brain’s
biology is challenging
Ideas, moods, feelings, etc. are biological phenomena
Localization of Function:
- Psychologists have moved away from phrenology to a more modern
understanding of localization (one part of the brain does this compared
to another)
While Franz Joseph Gall’s notion of phrenology was incorrect, the
concept of phrenology is important.
Biology, behaviour and mind:
- A critical analysis of what parts of the brain are responsible for certain
actions is a cogent endeavour
When we work from a biological POV, we can study links between
biological activity in the brain and psychological events
- Humans are biopsychosocial systems
Cells organize to form our organs and these organs from larger
systems for digestion, circulation, etc.
These systems form a larger system, an individual human being
who perceives the world uniquely.
Who is, in turn, part of a family, community, and culture
,Neural communication:
- Neurons: individual cells that receive, integrate, and translate
information
Communication between body and brain occurs via neurons
Different types of neurons in our bodies exist but all are
variations on the same general theme
Each type consists of a cell body and fibers:
Cell body (contains nucleus and acts like a tiny
factory for proteins and neurotransmitters)
Dendrites (look like branches, gather information
from other cells)
Axons (may have multiple terminals or just one,
transmits signals from soma to other neurons)
Branch-like dendrites receive electrical impulses from other
neurons and conduct them toward the cell body or “soma”
From there, a neuron’s axon transfers info through its terminals
to other neurons, or to muscles/glands in the body
Axons can be long, so dendrites “listen” and axons
“speak”.
- Like how electrical wires at home are insulated, so are some axons
when encased in a myelin sheath.
, Sheath is a layer of fatty material that insulates some axons
Regular spaces exist where stealth becomes thin or
nonexistent, these are called nodes of Ranvier
As myelin is laid onto different neurons until around 25 y/o which
is when neural efficiency and self-control grows.
Degeneration of myelin is part of the disease called
multiple sclerosis
Multiple sclerosis causes the immune system to
malfunction and attack glial cells that insulate
neurons in brain and spinal cord
Causes fatigue, vision problems, and movement
issues (speech difficulties, paralysis)
- Billions of glial cells support this process.
Glial cells provide nutrients and oxygen to neurons, as well as to
myelin
These stabilize neurons and destroy dead neurons and
pathogens because they are phagocytes (eat other cells)
In complex brains (dolphins, crows, people) the ratio of glia
to neurons is high when compared to less complex brains.
Depending on the location, different glial cell types make myelin.
, Schwann cells make myelin in the peripheral nervous
system (PNS) while oligodendrocyte do this in the central
system (CNS)
- Glial cells provide protection to the brain in three ways;
They produce cerebrospinal fluid, a colourless fluid surrounding
the brain and spinal cord
They form the blood brain barrier, which prevents foreign
material like some viruses and drugs from entering the brain
They contribute to the brain’s immune system.
While several molecular and morphological differences
exist between neurons in the PNS and CNS, the basic
myelin sheath arrangements are essentially the same
- A = Cell Body, B = Glial Cell, C = Axon
The Neural Impulse in General:
- Neurons transmit messages when they are stimulated by signals from
senses,
or when triggered by chemical signals from neighbouring
neurons.
- In response to stimulation, a neuron fires an electrical impulse called
an action potential
This is a brief electrical change that travels along an axon
