MBB1 EXAM QUESTIONS WITH VERIFIED
ANSWERS
Which of the following best describes the Platonic view of vision and the world?
Vision as Reflection - A 'real world' but our mortal senses are only capable of sampling a small
subsection of that world.
Which of the following is the alternative view which is illustrated in the writing of Friedrich Nietzsche?
Vision as Construction - There was no 'real world', only the world inside your head.
The world that we visually sense is entirely dependent upon...
Individual experience and perception. Our own retina perceives light properties from the objects
around us.
Excitation refers to...
The detection of different wavelengths from our immediate environment. AP stimulated along axon
of neuron in photoreceptors which continue message from one to next.
Sensation refers to...
An experience of events unique to each individual.
At what stage in the visual pathway is an action potential first generated?
When the image from the outside world is imprinted on the retina of the eye (photon becomes
receptor output). This sends signals to the primary visual cortex via action potentials.
What do L, M and S denote when applied to cones?
L = Long (red),
M = Medium (green),
S = Short (blue).
Cones that respond to different wavelengths of light.
What reason may you have for expecting the photoreceptors to be physically anchored on the retina
despite the observation that this means that there is neural matter between the light source and the
photoreceptor?
The retina consists of photoreceptors, bipolar cells, horizontal cells and ganglion cells - they are not
separate entities. This is our only contact with the world. Since photoreceptors receive the initial
input/stimulus from the environment, they must be 'anchored' down to retina to ensure it to be this
first point of contact. Each neuron can really only influence what it is connected to. Having them
anchored ensures the message is passed on rather than having them floating around aimlessly.
The presence of the blind spot.
A colour space is...
A method by which a particular light and colour may be represented such that its definition is unique
and replicable.
Orthogonality in the vector representation of signal coding confers which of the following properties
upon that stage of the system?
Orthogonality - a property that allows overlapping stimulus coding (e.g. location and quality).
, Which statement best describes a receptive field?
The sensitivity range (L) and area over which a cone will respond. Size and shape dependent on what
and how it will respond to a stimulus. (Cone = photoreceptor).
What is the most likely format of the first spatially structured (or differentiated) receptive fields in the
visual system?
Center-surround organization receptive field with excitatory receptors in the middle and inhibitory
receptors in the periphery. Increasing events in the centre of the receptive field increases the output
and vice versa.
The receptive field arrangement referred to in Question 12 confers what properties to the system?
Receptive fields provide the tool which we can cross boundaries of disciplines in vision to achieve
some kind of resonance in the data from different approaches - how you utilize components and
construct them into an apparent whole.
Ability to understand edges - ignores areas that are the same, acknowledges areas where there is
difference.
The term "opponency" refers to...
Colour opponency refers to the fact that there are three pairs of colours which have been described
as those that "cannot live with each other, and yet cannot live without each other."
Red-green, blue-yellow, white-black.
Refers to relationship between surround and centre of receptive field. Increasing in the surround
decreases the output, and increasing events in the centre increase the output, therefore the centre
and surround are opponent to one another.
Why, when considering the processing of the neural signal, is the actual physical location of any visual
neurone other than the photoreceptors, arbitrary?
Spatiotemporal volume - the properties of the receptive field are independent of the location of the
neuron since all receptive fields in the visual system have some relationship to the x,y,t space that
constitutes the axes of the visual input, but located at varying positions within the visual pathway.
Photoreceptors are our only like to the visual world. Once the photoreceptors have encoded the
relevant information, it doesn't make any difference where that information is processed.
Why, however, is the relative location of any sensory neurone potentially important?
Due to the other imagery being perceived first and detected by photoreceptors/neurons. Without this
initial point of contact, everything beyond this initial contact is lost since the image is lost; the relative
location of the sensory neuron is important because lines/contours next to each other in the "real"
world have to be represented next to each other in the mind, otherwise they would be random lines
and we wouldn't be able to work out shape, outline or further detail.
What is meant by the term "retinotopic mapping"?
Different regions of the retina are represented and processed by different areas within the primary
visual cortex, forming a retinotopic map.
The term "phase-coherence" refers to the hypothesis that...
An edge or border is signaled consistently across all scales of analysis.
ANSWERS
Which of the following best describes the Platonic view of vision and the world?
Vision as Reflection - A 'real world' but our mortal senses are only capable of sampling a small
subsection of that world.
Which of the following is the alternative view which is illustrated in the writing of Friedrich Nietzsche?
Vision as Construction - There was no 'real world', only the world inside your head.
The world that we visually sense is entirely dependent upon...
Individual experience and perception. Our own retina perceives light properties from the objects
around us.
Excitation refers to...
The detection of different wavelengths from our immediate environment. AP stimulated along axon
of neuron in photoreceptors which continue message from one to next.
Sensation refers to...
An experience of events unique to each individual.
At what stage in the visual pathway is an action potential first generated?
When the image from the outside world is imprinted on the retina of the eye (photon becomes
receptor output). This sends signals to the primary visual cortex via action potentials.
What do L, M and S denote when applied to cones?
L = Long (red),
M = Medium (green),
S = Short (blue).
Cones that respond to different wavelengths of light.
What reason may you have for expecting the photoreceptors to be physically anchored on the retina
despite the observation that this means that there is neural matter between the light source and the
photoreceptor?
The retina consists of photoreceptors, bipolar cells, horizontal cells and ganglion cells - they are not
separate entities. This is our only contact with the world. Since photoreceptors receive the initial
input/stimulus from the environment, they must be 'anchored' down to retina to ensure it to be this
first point of contact. Each neuron can really only influence what it is connected to. Having them
anchored ensures the message is passed on rather than having them floating around aimlessly.
The presence of the blind spot.
A colour space is...
A method by which a particular light and colour may be represented such that its definition is unique
and replicable.
Orthogonality in the vector representation of signal coding confers which of the following properties
upon that stage of the system?
Orthogonality - a property that allows overlapping stimulus coding (e.g. location and quality).
, Which statement best describes a receptive field?
The sensitivity range (L) and area over which a cone will respond. Size and shape dependent on what
and how it will respond to a stimulus. (Cone = photoreceptor).
What is the most likely format of the first spatially structured (or differentiated) receptive fields in the
visual system?
Center-surround organization receptive field with excitatory receptors in the middle and inhibitory
receptors in the periphery. Increasing events in the centre of the receptive field increases the output
and vice versa.
The receptive field arrangement referred to in Question 12 confers what properties to the system?
Receptive fields provide the tool which we can cross boundaries of disciplines in vision to achieve
some kind of resonance in the data from different approaches - how you utilize components and
construct them into an apparent whole.
Ability to understand edges - ignores areas that are the same, acknowledges areas where there is
difference.
The term "opponency" refers to...
Colour opponency refers to the fact that there are three pairs of colours which have been described
as those that "cannot live with each other, and yet cannot live without each other."
Red-green, blue-yellow, white-black.
Refers to relationship between surround and centre of receptive field. Increasing in the surround
decreases the output, and increasing events in the centre increase the output, therefore the centre
and surround are opponent to one another.
Why, when considering the processing of the neural signal, is the actual physical location of any visual
neurone other than the photoreceptors, arbitrary?
Spatiotemporal volume - the properties of the receptive field are independent of the location of the
neuron since all receptive fields in the visual system have some relationship to the x,y,t space that
constitutes the axes of the visual input, but located at varying positions within the visual pathway.
Photoreceptors are our only like to the visual world. Once the photoreceptors have encoded the
relevant information, it doesn't make any difference where that information is processed.
Why, however, is the relative location of any sensory neurone potentially important?
Due to the other imagery being perceived first and detected by photoreceptors/neurons. Without this
initial point of contact, everything beyond this initial contact is lost since the image is lost; the relative
location of the sensory neuron is important because lines/contours next to each other in the "real"
world have to be represented next to each other in the mind, otherwise they would be random lines
and we wouldn't be able to work out shape, outline or further detail.
What is meant by the term "retinotopic mapping"?
Different regions of the retina are represented and processed by different areas within the primary
visual cortex, forming a retinotopic map.
The term "phase-coherence" refers to the hypothesis that...
An edge or border is signaled consistently across all scales of analysis.
