Cognitive Neuroscience: 2000 Admission Exams

English is the language preferred by the Commission. Italian may be used if absolutely necessary. Please write clearly.
Please answer a total of 3 questions, which must consist of Question #1 and any two selected from Questions #2-15.
(1) Tell us about a publication in any scientific field that has had a major influence on you. The publication you choose need not necessarily be in cognitive neuroscience. Use the following format for your answer:

(a) title and authors (accuracy not required);
(b) the problem addressed in the paper;
(c) what was known about the problem before;
(d) the methods used to approach the problem;
(e) the main results;
(f) the authors' interpretation of the results;
(g) how this publication changed your way of thinking.
Alternatively, you may do the same exercise for a lecture that you have attended.
(2) Take any cognitive domain and discuss the consistencies and the contrasts between any two of

(i) brain imaging findings;
(ii) neuropsychological findings from brain-damaged patients;
(iii) cognitive psychological evidence.
(3) Take a model of any cognitive function and describe how you would go about testing model-based predictions that have not yet been considered, using a single case approach.
(4) Take any one neurological syndrome. Describe its characteristics and discuss its theoretical significance for our understanding of how the normal mind-brain works.
(5) Are symbolic and connectionist models of cognitive functions incompatible? Take any one area of cognition and assess which type of model, or neither or both is most effective in explaining findings from both the effects of neurological impairment and normal experiments.
(6) Briefly describe the mechanisms and factors controlling synaptic plasticity.
(7) Discuss the proposal that neurotrophic factors are involved in neuronal survival and neuronal differentiation.
(8) Design an experiment to test the possibility that a predefined brain region is involved in visual form recognition, in monkeys. Also describe the training schedule, if training is needed.
(9) Is there a "supervisor" in the flow of sensory information which orients a motor act towards a sensory stimulus? Which experimental evidence might support or deny either possibility?
(10) A 1 mm-diameter column of cerebral cortical tissue contains about 10,000 neurons, arranged in layers, forming something like 1 billion synapses.What are some of the basic operations carried out by a cortical column? Localization of function is a fundamental principle of cerebral cortex. Are the functional diffferences between cortical regions due to differences in the operation of the columnar units that comprise them? Alternatively, if the columnar units function in a similar manner, what might account for cortical functional specializations? Give concrete examples.
(11) You are asked to provide some of the hyperlinks for the new Dictionary of Cognitive Neuroscience on CD-rom. Specify 3 nouns to which you would like to associate the adjective "associative", and provide brief descriptions (e.g., 100 words) of how the adjective qualifies each of the nouns.
(12) Your lab happens to have at its disposal a 100-channel recording systems, which can be used with electrodes of any configuration, and the intent is to record from as many neurons as possible in a brain region in which they are tightly packed. If you use 100 distant electrodes, each of them will be able to record from 1 or at most 2 nearby cells, but the signal from more distant cells will be below the noise level. If you use electrodes spatially closer, instead, several of them may pick up the signal from the same cells, enabling better separation of faint signals; but if they are too close they will all sample the same few cells. Regarding electrodes as point-like and disregarding considerations of tissue damage, write how you would go about formalizing your dilemma as a mathematical optimization problem.
(13) Briefly describe an experiment to investigate whether, at birth, the functional properties of the cortex in human infants are organized like those of adults.
(14) It is already late on the sixth day of Creation, and the Almighty decides to provide behemas, a mammalian species, with a rudimentary sound communication system, to help them face the threat posed by the newly created human race. The Almighty reckons that if behemas are to use P distinct phonemes, it will take them a time of order of the square root of P msec to produce each of them in a way that cospecifics will tell it apart from the other phonemes. How many phonemes should behemas be endowed with, for optimal speed of communication? And if a fraction q of phoneme pairs can be uttered consecutively in a time 25 percent less than twice the time to utter them separately, for which values of q (as a function of P) would it be convenient for behemas to use such dipthongs instead of the original phonemes?(Please note that the Almighty had already formulated a mathematical theory of communication on day 4, although it was reinvented independently by Claude Shannon 5708 years later).
(15) People suffering from motor neuron disease or spinal cord injury would benefit from a technology that would utilize brain signals to control external devices, such as a joystick. Suppose that you have access to neuronal activity recorded at 100 electrodes, implanted chronically in the hand/arm region of primary motor cortex. Describe how you would "decode" this neural activity to control an external device in realtime.