Tài liệu hạn chế xem trước, để xem đầy đủ mời bạn chọn Tải xuống
1
/ 156 trang
THÔNG TIN TÀI LIỆU
Thông tin cơ bản
Định dạng
Số trang
156
Dung lượng
1,31 MB
Nội dung
[...]... phenomenon exploded on the scene, it mostly settled on a class of ultrasimple models that didn’t meet any of these criteria Most neural networks consisted of a small number of neurons connected in three rows A pattern (the input) is presented to the first row These input neurons are connected to the next row of neurons, the so-called hidden units The hidden units then connect to the final row of neurons,... smaller fraction of cells, we can see the six layers I mentioned These layers are formed by variations in the density of cell bodies, cell types, and their connections All neurons have features in common Apart from a cell body, which is the roundish part you imagine when you think of a cell, they also have branching, wirelike structures called axons and dendrites When the axon from one neuron touches... assumed that if one region is used for language and another for vision, then there ought to be differences between those regions If you look closely enough you find them Regions of cortex vary in thickness, cell density, relative proportion of cell types, length of horizontal connections, synapse density, and many other ways that can be tricky to discover One of the moststudied regions, the primary... row of neurons, the output units The connections between neurons have variable strengths, meaning the activity in one neuron might increase the activity in another and decrease the activity in a third neuron depending on the connection strengths By changing these strengths, the network learns to map input patterns to output patterns These simple neural networks only processed static patterns, did not... Astonishing Hypothesis The astonishing hypothesis was simply that the mind is the creation of the cells in the brain There is nothing else, no magic, no special sauce, only neurons and a dance of information I hope you can get a sense of how incredible this realization is There appears to be a large philosophical gulf between a collection of cells and our conscious experience, yet mind and brain are one... reconcile bank transactions, it is all 1’s and 0’s underneath, and any Turing Machine can be programmed to handle it Information processing is information processing is information processing All digital computers are logically equivalent Turing’s conclusion was indisputably true and phenomenally fruitful The computer revolution and all its products are built on it Then Turing turned to the question... wrong way to tackle the problem Intuitively I felt that the artificial intelligence approach would not only fail to create programs that do what humans can do, it would not teach us what intelligence is Computers and brains are built on completely different principles One is programmed, one is self-learning One has to be perfect to work at all, one is naturally flexible and tolerant of failures One... the same operation The thing that makes the vision area visual and the motor area motoric is how the regions of cortex are connected to each other and to other parts of the central nervous system In fact, Mountcastle argues that the reason one region of cortex looks slightly different from another is because of what it is connected to, and not because its basic function is different He concludes that... interests But I quickly became disillusioned with the field By this time I had formed an opinion that three things were essential to understanding the brain My first criterion was the inclusion of time in brain function Real brains process rapidly changing streams of information There is nothing static about the flow of information into and out of the brain The second criterion was the importance of feedback... the notion that the cortex consists of many functional regions or functional areas The terms are equivalent We have learned a lot about functional areas in the past century, but much remains to be discovered Each of these regions is semi-independent and seems to be specialized for certain aspects of perception or thought Physically they are arranged in an irregular patchwork quilt, which varies only a . 2004 by Jeff Hawkins and Sandra Blakeslee All rights reserved. Distributed in Canada by H. B. Fenn and Company Ltd. Library of Congress Cataloging-in-Publication Data Hawkins, Jeff, 195 7- On intelligence. relationships and making predictions based on those memories. It is this memory-prediction system that forms the basis of intelligence, perception, creativity, and even consciousness. Intelligence. These input neurons are connected to the next row of neurons, the so-called hidden units. The hidden units then connect to the final row of neurons, the output units. The connections between neurons have variable