Further questions for chapter 03 - suggested answers
Q. Explain why cross-lesion disconnection experiments help make more precise inferences about the function and specialization of specific areas of the brain.
A. The damage done to the brain is made more precise by targeted lesions, rather than simply observing the effects of brain damage from some other cause. This type of selective lesioning can also be used to identify the pathway of information processing in the brain (as shown in Ungerleider and Mishkin’s experiments). This is done by removing areas in opposite hemispheres of the brain along the hypothesized pathway of information. Removing areas from both hemispheres with the same hypothesized function should “knock out” that function entirely. Removing areas from both hemispheres that possess different functions at different points along the pathway of information processing should not have an effect, however, since the hemispheres of the brain communicate through the corpus callosum.
Q. Explain what about parallel processing networks makes them parallel. Also explain why this is important.
A. Parallel processing is parallel because the flow of information through a network is determined by what happens in all the units in a given layer of the network, even though none of the units are connected to each other directly. This is important because it allows for training and learning. It is also retains important aspects of associationism.
Q. Explain the differences between neurological and cognitive models of information processing for single-word learning.
A. The neurological model is serial. It also ties information states to specific physical states. The cognitive model is parallel. It also relies on the idea that information flow is realizable across multiple different types of physical states.