Zusammenfassung der Ressource
Neural basis of learning
- Neural pathways
- Learning:Learning is
defined as a relatively
permanent change in
behaviour that occurs as a
result of experience
- Learning is an ongoing process
that continues throughout the life
span, enabling us to adapt and
cope in an ever-changing world.
Learning may occur intentionally
or unintentionally and can also be
active or passive.
- When a neuron is stimulated it produces an
action potential and when the action potential
gets to the end of the axon terminals of the
presynaptic neuron it stimulates the release of
a neurotransmitter called GLUTAMATE into the
synaptic gap between the presynaptic neuron
and the dendrites of a neighboring
postsynaptic neuron.
- neurotransmitter
strengthens connections
- dopamine:release of dopamine
at this time provides a
pleasurable experience. This
positive consequence rewards
the activity motivating the
individual to repeat it.
- repeated stimulation
- Hebbian learning: if two
neurone are active at the
same tie, the synapse
between them are
strengthened, thus
facilitating the passage of
nerve impulses along a
particular circuit.
- long term potentiation: Hebb's hypothesis lead
to the discovery go LTP-refers to long-lasting
strengthening of the synaptic connections of
neurons, resulting in a more effective functioning
of the neurons whenever they are activated. LTP
is a crucial neural mechanism that makes
learning possible.
- as the brain receives
specific appropriate input
through the senses or
processes information, with
appropriate frequency,
intensity and duration, the
brain physically changes its
structure
- Neurons
- Proliferation is the first
processes, which refers
to the production of new
cells/ neurons in the
brain primarily occurring
early in life.
- Early in development, the cells lining
the ventricles divide where some cells
become stem cells where others
remain where they are or become
neurons.
- Migration, which refers to
the movement of newly
formed neurons and glia to
their eventual locations.
- Migration occurs in a
variety of directions
throughout the brain
and cells following
chemical paths in the
brain
- Myelination occurs
which is the process by
which glia produce the
fatty sheath that covers
the axons of some neurons
called the myelin sheath
and occurs gradually for
decades.
- synaptogenesis that
refers to the
formation of the
synapses between
neurons.
- synaptogenesis occurs
throughout the life as
neurons are constantly
forming new
connections. The process
slows significantly later in
the lifetime.
- plasticity : refers to the
brains ability to change
and reorganise itself by
forming new neural
connection throughout
life
- developmental
plasticity :brains
natural ability to
form new
connections in order
to process sensory
information from
environmental
stimulation
- synaptic pruning:
eliminates weaker
synaptic contacts
while stronger
connections are kept
and strengthened
- adaptive plasticity: is the
brains ability to form new
connections to recover or
compensate for lost function
and\or to maximise
remaining functioning in the
event of brain injury
- Axonal sprouting:
undamaged axons
grow new nerve
endings to reconnect
neurone whose links
were injured or
severed
- rerouting : undamged neurone that has
lost connection with an active neurone
may seek a new active neurone and
connect with it instead
- structure
- soma
- dendrites
- axon
- myelin sheath
- axon terminal
- synaptic gap
- neurotransmitter
- post synaptic neuron
- Maturation and development
- maturation: involves the orderly,
sequential changes the body is
genetically predetermined to
undertake
- critical periods:optimum
times for the development of
certain pathways in response
to appropriate stimulation
- sensitive periods: when an
organism is more responsive to
certain environmental stimulus
or experiences
- experience
dependent
learning
- particular learning
- experience
expectant
learning
- experience
=
unexpected
- reflex: innate, automatic reaction
involving a simple rapid response to a
specific stimulus, which does not depend
on conscious thought or processing