MBB1 sensation and perception exam questions

[chiral]

Hey guys,

I hope there are people doing MBB1 here so we cld work on the exam questions together
I'm posting up all the questions, share your ideas/thoughts/confusions etc. I'll be posting up my answers once i start answering which would probably be about next week sometime. However I thought i'll post the questions up now for those who are eager and are starting now

Please only use this thread to answer questions and ideas on the questions otherwise it will get too messy.

1. Which of the following best describes the Platonic view of vision and the world?
2. Which of the following is the alternative view which is illustrated in the writing of
Friedrich Nietzsche?
3. The world that we visually sense is entirely dependent upon……
4. Excitation refers to…….
5. Sensation refers to…….
6. At what stage in the visual pathway is an action potential first generated?
7. What do L,M and S denote when applied to cones?
8. 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?
9. A colour space is……
10. Orthogonality in the vector representation of signal-coding confers which of the
following properties upon that stage of the system?
11.Which statement best describes a receptive field?
12.What is the most likely format of the first spatially structured (or differentiated) receptive
fields in the visual system?
13.The receptive field arrangement referred to in Question 12 confers what properties to
the system?
14.The term “opponency” refers to…..
15.Why, when considering the processing of the neural signal, is the actual physical
location of any visual neurone other than the photoreceptors, arbitrary?
16.Why, however, is the relative location of any sensory neurone potentially important?
17.What is meant by the term “retinotopic mapping”?
18.What is meant by “tonotopic mapping”?
19.The term “phase-coherence” refers to the hypothesis that…..
20.The idea of modularity in visual processing refers to……
21.What reason may you have for questioning the assumption that the LGN is just a relay
station for signals traveling from the retina to the cortex?
22. Taken as a population, primary visual cortical (v1) neurones have what critical
property?
23. An example of context-dependency in vision is......
24. What is red?
25. An attentionally-controlled motion system may….
26.The visual system appears to dissociate motion-signals elicited by eye-movements or
from retinal motion by.....
27. The spatial structure of natural textures is consistent with the properties of the system
because……
28. “Place theory” in hearing refers to…..
29. “Frequency theory” in hearing refers to…..
30. “Adaptation” refers to...
31. What is meant by the term “parallel processing”...
32. The terms M and P in the context of the visual system refer to....
33. A form of parallel processing in the auditory system is implemented in the cochlear
nucleus by…….
34. Information is...
35. A vector is...
36. One critical similarity between the visual and auditory systems is ……..
37. One critical difference between visual and auditory systems is……..
38.Which two structures or processes exploit the properties of orthogonality in their
operation?
39. What aspect of the relationship between the stimulus and the cortical representation is
different between vision and audition
40. The theoretical hierarchy established by David Marr is……
41. “Retino-cortical expansion” refers to.....
42. The two most likely kinds of motion detector in the human visual system are called….
43. The three critical dimensions of vision are…
44. The term “Biological motion” describes…..
45. Interaction between V1 orientation-selective receptive fields follows what ʻlawsʼ?
46. The visual system is sensitive to……
47.What critical neural interaction is affected by, among other things, hallucinogenic
drugs?
48. Your experience of reality is…..
49. Synaesthesia is….
50. One fish, two fish,…….

[foolishangel]

hey, i've got most of the answers, but need help with a few

[anonymous1]

hey foolishangel,

i am doing them on Saturday so i'll post up my answers then, we can compare and maybe I will be able to help you with the ones you don't get

[unigirl101]

Hey guyssss, I'm also trying to do the questions and I have no idea if my answers are even on the right track. If someone could please post their answers now, seriously whatever you've got, I would appreciate that so then I can check to see I'm on the right track, and then when I work out my answers I'll post them all  thanks!

[kitkat93]

Hey everyone there are also a few questions that i am still unsure on but have done most of the answers so if we could exchange answers that would be amazing

[anonymous1]

^I'll be exchanging tomorrow night when i go through them all 

I'll post them then

[anonymous1]

1. Vision: as a reflection of what is out, however good your reflection is your perception is enhanced
2. The other end is- vision and construct of reality is a product of the brain and there is no external world it is just in your head. For example when you dream your in a reality that is purely inside your head. We all have internal thoughts going on. Vision as a constructive process.
3. Individual experience
6. In the ganglion cells of the retina
7. They denote cones that respond optimally to long, medium or short wavelength light (roughly red, green and blue in that order). It's called the trichromatic theory of vision and it's all very clever: Because the distributions of the cone's responses overlap your brain can use mean firing to infer the actual wavelength. Anyway, the short and simple answer is L=long, M=medium and S=short.
11. Sheet of photo receptors
The part of the visual world that the neuron is responsive to (that it "sees").
What the visual stimulus needs to be in order to elicit spikes.
14. 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”. They are red-green, blue-yellow, and white black. For, as most people know, when we look at a green surface for a brief period of time and then transfer our gaze to a neutral, blank, screen the colour of the after image is red. A yellow surface will produce a blue after image and a white surface a black one.One explanation of these opponent effects – the one most often repeated – is that they are due to adaptation in the retina. The explanation here is something like this: that a green surface reflects more green light, leading to the adaptation of the “green” or middle wave receptors. Thus adapted, the activity in the opponent “red” receptors holds sway. The result – we perceive red.
17. In lower visual areas (e.g., V1 through V5) the neurons are organized in an orderly fashion called topograpphic or retinotopic mapping, in the sense that they form a 2D representation of the visual image formed on the retina in such a way that neighboring regions of the image are represented by neighboring regions of the visual area.
18. tonotopy (from Greek tono- and topos = place) is the spatial arrangement of where sounds of different frequency are processed in the brain. Tones close to each other in terms of frequency are represented in topologically neighbouring regions in the brain. Tonotopic maps are a particular case of topographic organization, similar to retinotopy in the visual system.
20. In cognitive neuroscience, visual modularity is an organizational concept concerning how vision works. The way in which the primate visual system operates is currently under intense scientific scrutiny. One dominant thesis is that different properties of the visual world (color, motion, form and so forth) require different computational solutions which are implemented in anatomically/functionally distinct regions that operate independently – that is, in a modular fashion.
28. The Place theory, in its most modern form, states that the inner ear acts as a tuned resonator which extracts a spectral representation of the incoming sounds which it passes via the auditory nerve to the brainstem and the auditory cortex. This process involves a tuned resonating membrane, the basilar membrane, with frequency place-mapping. In other words, each position on the basilar membrane is associated with a particular characteristic frequency (CF)
29. Early forms of the frequency theory were sometimes referred to as telephone theories and assumed that the auditory nerve passed complete time domain representations of the incoming acoustic signal to the brain in a manner analogous to the way the waveform of a speech sound is transformed into fluctuating voltages in a telephone line. This theory assumes that a complete time domain representation of the incoming waveform is directly encoded in the pattern of firings of the auditory nerve.
31. Parallel pathways generally exhibit these 4 main characteristics:
1.   Physiologically/functionally distinct. For example, the M cells conduct neural signals faster, while P cells represent more constant stimulus presence. A simple hypothesis is that M cells contribute to fast/transient processing (visual motion perception, eye movements) while P cells contribute more to recognition (object recognition, face recognition, etc).
2.   Anatomically distinct. The dendritic trees of P cells are always smaller than the M cells (remember that they're also called "midget" cells). Note that dendritic trees of both types of cell get larger as you move from fovea to periphery.
3.   Complete coverage (or nearly complete). Both M and P cells cover the entire retina.
4.   Recombine. The M and P cells are separated in the LGN (different layers) but recombine in visual cortex (although some separation still exists)
32. Retinal ganglion cells actually come in 2 sorts: M (magnocellular, or parasol) and P (parvocellular, or midget).
•   P cells also exhibit color-opponent responses: their firing is also dependent on the wavelength of light in their receptive field. M cells do not exhibit color-opponency.
•   M cells make transient responses: they fire action potentials when a stimulus is introduced, but quickly fade if the stimulus does not change. P cells, meanwhile, give sustained responses to stimuli in their receptive field.
35. A quantity having direction as well as magnitude, esp. as determining the position of one point in space relative to another.
48. subjective
49. A rather peculiar condition in which the senses get cross-wired. For example, a person with synethesia may see colours when they hear a sound, or can actually taste words; stimulation of one sense, it seems, causes an inappropriate stimulation of another.

That is what I have done thus far, if anyone has the other answers please post them up, it'll save everyone time

and if anyone wants to make any corrections please do so

[xyling]

Got some answers here that i have worked out. Feel free to correct me if i'm wrong.

6. 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 ie a photon becomes a receptor output. That sends signals to the primary visual cortex via action potentials

9. A colour space is defined as a method by which a particular light and colour may be
represented such that its definition is unique and replicable

12.What is the most likely format of the first spatially structured (or differentiated) receptive fields in the visual system?
Center-surround organization (2D donut shaped) receptive field with ON-receptors (excitatory) in the middle and OFF-receptors (inhibitory) in the periphery. Increasing events in the centre of the receptive field increases the output and vice versa.

13.The receptive field arrangement referred to in Question 12 confers what properties to the system?
Cone opponency?

15.Why, when considering the processing of the neural signal, is the actual physical location of any visual neurone other than the photoreceptors, arbitrary?
This is an issue of 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 link to the visual world. Once the photoreceptors have encoded the relevant information it doesn't make any difference where that info is processed

16.Why, however, is the relative location of any sensory neurone potentially important?
This is because any other imagery that we perceive is first and foremost detected by the photoreceptors/neuron. Without this initial point of contact, everything else does not exist since all direct contact with the image is lost; the relative location of any 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 just be random lines and we wouldn't be able to work out for example the outline and consequently the shape of something.

19.The term “phase-coherence” refers to the hypothesis that an edge or border is signaled consistently across all scales of analysis.

21.What reason may you have for questioning the assumption that the LGN is just a relay station for signals traveling from the retina to the cortex?
There are more connections carrying signals from the cortex BACK to the LGN than from the LGN to the cortex.

22. Taken as a population, primary visual cortical (v1) neurones have what critical property?
Also known as striate cortex. V1 represents everything that one is able to see as all visual input to the cortex enters at this point. Output of individual neurons at this stage is still not very specialized since data is represented in a fairly general way. Higher cortical areas ie V2 onwards modifies responses of neurons from V1.

23. An example of context-dependency in vision is straight matchsticks arranged into a curve gives the whole impression of a curve even though individual matchsticks are straight.

24. What is red?
Red is a colour that is subjective and its perception varies depending on the experience of each individual. The world we perceive is a construct of the operation of the system and hence red to me would be a different hue/shade to someone else just because of the perceptions and associations we form to the colour.

30. “Adaptation” refers to reduced sensitivity to stimulation as a result of repeated exposure to stimulus.

31. What is meant by the term “parallel processing”?
The ability of the brain to do many things/processes simultaneously. Eg identifying an object requires colour, depth, form, motion etc. A black car is only seen as a black car when there is a combination of various inputs from different parts of the visual system.

[anonymous1]

Thanks xyling!

we don't have much left anymore

The ones remaining are: 4,5, 8, 10, 25, 26, 27, 33, 36-47

if anyone has the answers to the above could you please post them and if anyone finds any corrections please feel free to correct

[mbb1student]

Hiya, thanks so much for everything up thus far, I think it fantastic that we can discuss these tricky (and difficult to find and revise) questions.

In contribution, firstly I wonder if q. 26 has something to do with motion with delays and multipy. (stuff covered in lecture 5, one can look at the slides to see about it not just having to listen to the lectures)

Secondly, I think Q. 40 (D Marr) is - The theoretical hierarcy established by Marr is that it is more effiecient to analyse a complex imput parallel in term of its fundamental modules than in serial (bott of hierarcy). Therefore, parallel is top of hierarchy, serial (bottom of hierarchy) (lecture 7) I'm pretty sure this is his theoretical hierarchy.             

What do you say? I'm just trying to find the answers and help. I hope they're not completely off, well my answer to q. 40 is certainly not.  Cheers!

[mbb1student]

It's funny beacuse we have no idea which perpective the question is coming from or rather the possible answers, if you know what I mean, for example, in answer to question 3 (The world that we visually see is entirely dependent upon...), anonymous 1 stated Individual experience, which I hadn't thought of and which I think is good, I thought the possible answers (a,b,c,d) would be like (the world we visually see is entirely dependent upon)- The retina, which is the only contact we have with the world. (Of course photo receptors absorb fotons on the back of the retina and that's how we see.)

I also thought I'd add my take on question 14 (Opponency)Opponency refers to the relationship between the surround and the centre of a recpeptive field. INcreasing in the surround decreases the output, and increasing events in the centre increases the output, therefore the centre and surround are opponent to one another. 

As I recognise that we don't know the possible answers for each question I suppose it is best to have a few ideas, anyway I dunno. Like in question 1 about the Platonic view, he might provide four different analogies and then expect us to apply theory, but that wouldn't be very hard given that the first two questions are seemingly easy. (Hopefully they're as easy as I think!)
Damn! I wish more people could contribute to this questioning we're doing and get some of the rest going.

[Gloamglozer]

It's funny beacuse we have no idea which perpective the question is coming from or rather the possible answers...

Hence why I think subject-wise, not area of study, it is an Arts subject and not a science subject.  Also, it's not as cheap as other science subjects either.  I have a feeling the uni is charging it as an arts subject.

[anonymous1]

@mbb1student

thanks for the corrections and your views it's really appreciated.
I wish there were more people contributing too, maybe there isn't many MBB1 students around...?

[paulsterio]

What's MBB1?

[Gloamglozer]

What's MBB1?

Mind, Brain and Behaviour 1.

Basically first year, first semester psychology.  So no prizes for guessing what MBB2 is.