Synapse 2

Question 1

How do dendrites help compute the response of the neuron?

Answer 1

Timing and multiplicity of inputs

Dendritic morphology and position of synapse

Different types of electrical activity

Question 2

Where are IPSP attached to cause the most inhibiting response?

Answer 2

On the cell body- soma

Question 3

How does dendritic spine length effect PSPS?

Answer 3

Less ESPS

Question 4

What are dendritic spikes?

Answer 4

Another form of electric activity in dendrites

Self propagating

Question 5

What is the benefit of a dendritic spike?

Answer 5

Increases response of EPSPs

Long term potentiation- building connections

Question 6

What can cause an action potential?

Answer 6

2 coincident EPSPs.

Question 7

What does the strength of the PSP depend on?

Answer 7

Placement and excitatory or inhibitory nature of the inputs.

Question 8

What determines the level of excitation?

Answer 8

Dendrite structure and synapse location.

Question 9

What does dendritic spine morphology influence?

Answer 9

PSP summation.

Question 10

What does PSP stand for?

Answer 10

Post synaptic potential.

Question 11

Does dendritic spine length influence EPSP summation?

Answer 11

The longer the spine the lower the EPSP.

Question 12

What are EPSPs and IPSPs important in?

Answer 12

They are passive electrical activity important for setting the axonal response.

Question 13

What are the other forms of electrical activity in the dendrites?

Answer 13

Self propagating dendritic spikes.

Question 14

What does the dendritic spike do?

Answer 14

Boost the depolarization in the dendrites.

Question 15

When do dendritic cells occur?

Answer 15

Especially when stimulation is intense in space or time.

Question 16

How can dendritic spikes stimulate an action potential?

Answer 16

They can leak into the cell body to stimulate an AP.

Question 17

Do dendritic spikes act locally?

Answer 17

They are thought to act locally on postsynaptic membranes to generate LTP.

Question 18

What is memory due to?

Answer 18

Strengthened synapses and making of new synapses.

Question 19

What is required to reach the threshold?

Answer 19

Spatial and temporal summation of multiple PSPs/dendritic spikes.

Question 20

What does stronger synapses result in?

Answer 20

Increased: NT release, sensitivity, number of receptors and size of post synaptic machinery.

Question 21

What does LTP stand for?

Answer 21

Long term potentiation.

Question 22

What is LTP associated with?

Answer 22

Making new synapses in vivo.

Question 23

How are stronger synapses formed?

Answer 23

Upregulation of NT secretion and receptor expression.

Question 24

How are more synapses made?

Answer 24

Sprouting, branching and dendritic spine formation.

Question 25

What is Hebb's learning rule about correlation?

Answer 25

Correlated pre and postsynaptic activities cause synapse to strengthen.

Question 26

What is Hebb's learning rule about uncorrelation?

Answer 26

Uncorrelated pre and postsynaptic activities cause synapse weakening.

Question 27

Why could synaptic change occur?

Answer 27

Because of neuronal activity at critical points within a behavioural brain pathway.

Question 28

What is a good example of changes in behavioural learning?

Answer 28

Addiction.

Question 29

What could be these synaptic changes?

Answer 29

Increases and decreases in synaptic strength leading to behavioural plasticity.

Question 30

How can drugs be addictive?

Answer 30

Drugs can cause massive release of dopamine in the reward centre.

Question 31

What starts the behavioral changes when introduced to an addictive drug?

Answer 31

Synaptic plasticity in glutaminergic synapses.

Question 32

What is the reward centre?

Answer 32

The nucleus accumbens.

Question 33

What are the types of inhibition in multi-neuron networks?

Answer 33

Lateral inhibition, feedforward inhibition, feedback inhibition.

Question 34

What are the types of excitation in multi-neuron networks?

Answer 34

Feedforward and feedback/recurrent.

Question 35

What start the knee jerk reflex?

Answer 35

By tapping the tendon connected to the quadricep which stretches the muscle.

Question 36

Describe pyramidal cell firing.

Answer 36

It is under strict time control to prevent run away excitation.

Question 37

How are the pyramidal cells inhibited?

Answer 37

Done by feedforward and feedback inhibition.

Question 38

What do inhibitory microcircuits involve?

Answer 38

Interneurons and short axons.

Question 39

What are the properties of inhibitory microcircuits?

Answer 39

Fast acting and inhibition is mostly by GABA.

Question 40

Where are central pattern generators?

Answer 40

In the spinal cord.

Question 41

What are the central pattern generators used in?

Answer 41

Communication in white matter in spinal cord.

Question 42

What is an example of central pattern generators?

Answer 42

Alternating rhythms for walking generated in the spinal cord.

Question 43

What is an example of inhibitory interneurons for pain?

Answer 43

Stimulation of touch can help to block transmission of pain impulses to the brain.

Question 44

How can touch decrease pain?

Answer 44

Touch fibres stimulate inhibitory interneurons to decrease activity in axons of pain fibres.

Question 45

What affects the degree of convergence?

Answer 45

The more dendrites a neuron has, the higher the degree of convergence.

Question 46

What are examples of neuronal convergence in a circuit?

Answer 46

Pyramidal cells and Purkinje fibres.

Question 47

What are pyramidal cells?

Answer 47

A type of multipolar neuron found in areas of the brain.

Question 48

Where in the brain are pyramidal cells found?

Answer 48

The cerebral cortex, hippocampus and amygdala.

Question 49

What is neuronal divergence?

Answer 49

Information from a single neuron is passed to a number of other neurons simultaneously.

Question 50

How is sensory information diverged?

Answer 50

Sensory information arriving at the somatosensory cortex can be diverged widely through the cortex.