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Chapter 2: In Unfamiliar Territory Without a Guide





¤ What supervised learning situations reveal about the profound difficulties of

unsupervised learning (relevance, importance, ordering, and reliability of information).



¤ Particular characteristics of classroom learning and child-directed speech.



¤ Safe and unsafe learning environments.



¤ Making difficult perceptual learning more tractable.



¤ Heuristics from the golden age of learning theory for simplifying the problem of

learning without supervision (and taking advantage of supervision when available).





Chapter 3: The importance of objects

 How essential it is to be able to treat things as the same, and hence the importance

of perceptual learning

 Why this seems easy to us despite how difficult it is

 To illustrate the challenges and the impressive and powerful way in which they

are handled in the human brain, we tell the story of how Hebb developed his

theory of cell assemblies





Cooperation through competition

 How cell assemblies form

 How cell assemblies function

 A puzzle - why human infants are guaranteed to be incompetent

 The slow, conservative nature of perceptual learning

 Diffuse activity becomes focused and organized as cell assemblies form

 Flexibility-competence tradeoff

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Putting the pieces together: Building models



 Cognitive maps

 Associations

 Sequence

 Hierarchy

 Horizontal and vertical structure

 Affective coding



Slow learning, active learning and other challenges



The slow, conservative nature of the learning process, while essential for perceptual

generalization, creates a potentially serious handicap. There are times when a faster

learning rate is not merely desirable, but essential. If a given cave happened to house a

bear that one narrowly escaped from when one innocently wandered by, avoiding that

cave in the future has to be learned immediately, and not with the usual requirement of

multiple repetitions of the experience. Clearly some way to override this conservative

mechanism when appropriate is called for. The continuation of the closed loop activity

of the cell assembly provides a substitute for repetitions in the environment.

Consolidation is what we call this means of achieving the repetition required for learning

in the mind rather than in the world that can be used as an override mechanism. One

need not have certain experiences repeatedly if, when an instance does occur,

consolidation provides the necessary multiple repetitions.



Not sure if we want to include mention of Keppel, but if we do perhaps the following

would be helpful:



Do we get to learn, or is all up to our internal mechanisms?



The consolidation process is a central actor in the way internal supervision takes

place. However some years ago a distinguished student of the learning process

expressed not only his personal opposition to such a mechanism, but what he felt

was the opposition of most experts in this area. The reason he cited: the distaste

for thinking of learning as a process in which an individual plays no active role.

This distaste motivates an attack on a series of studies that seems to provide

evidence for such a built-in mechanism. Yet the authors of this series of studies

themselves have emphasized the role of active learning. What‟s going on here?



THINGS TO RAISE:

1. The criticized studies are sound

2. There must be a built-in mechanism

3. There is no conflict between active learning and a built in mechanism

4. A key source of the misunderstanding is a failure to distinguish levels of

mechanism

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Positive Feedback: Utilizing the Benefits and Managing the Risks

 The blow-up problem



 The dynamic trace



 PIWIT



 Regional inhibition



 How the brain flexibly and automatically shifts from parallel to serial and back as

the circumstances require



 Limited capacity and competition serve as a means of maintaining focus despite

the awesomely parallel capability of the perceptual systems.





Limited capacity and the control of clutter



Gibson's challenge - the more one knows about something, the longer it would take to

think about it?



Dealing with new information about old things

 How to handle new information that is in some way different from what one had

learned previously. Both updating and refining skills depends upon modifying the

information one has stored rather than merely adding to it.

 Catastrophic forgetting



Structural clutter

 keeping stored information up to date without being overwhelmed with

information

 PIWIT

 CLR



Dynamic clutter

 turning off persistent activity in a cell assembly

 fatigue

 Zeigarnik effect

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The quest for clarity



What are the key motivational and emotional inclinations that an information-oriented

organism needs?



Inclined to seek opportunities to explore new things and make sense of them without

endangering yourself by getting in over your head



Exploratory inclinations

Curiosity

Boredom



Safety enhancing inclinations

Detest being confused



Clarity seeking inclinations

Figuring something out is pleasurable



How the clarity mechanism provides these inclinations and guides behavior



How the clarity mechanism works to detect the state of the system



Mention automaticity in this summary? Mention that clarity is often guiding us without

our awareness?





Outcome sensitive learning

Through a mixture of arousal, pleasure and pain, clarity and environmental impact, it is

possible to describe a set of heuristics that could make identifying “importance” feasible.

What we are proposing is that the only practical way to approach this problem is to

generate heuristics, rules of thumb. In a world where the future cannot be known and

decisions as to whether to store information or not must be made nonetheless, these best

guesses are remarkably suited to this difficult task.

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Control mechanisms

Roughly speaking, control mechanisms achieve one or more of the following goals:

1. Prevent the system from going awry

2. Managing and normalizing thoughts and inputs to keep them within the bounds

that the system can handle

3. Allocation of cognitive resources – essential due to the small brain/big world

challenges

4. Setting brain „operating parameters‟ appropriate to current goals, knowledge,

and environmental conditions



The need for detecting system-level states that require attention and perhaps intervention



How clarity and metacognition detect these states



Something about metacognition



Attention



Clarity failure -- a decline in clarity that is large and/or of rapid onset -- and its

management





Pursuing Our Purposes



¤ The ceaseless scheduling problem of working out how much time and energy to

allott to a myriad of possible purposes, behaviors, and thought processes.

¤ Will-power, temptation, and delay: why can‟t humans simply determine whether

or not delaying is advantageous in a particular situation and, if so, do it without fussing?

Why should this be difficult? What are the properties of the brain that make delaying an

unpleasant (and not infrequently unsuccessful) struggle?

¤ The evolution of will-power in social control.

¤ Will-power as a limited mechanism

¤ Will-power as an enabling technology co-opted for new purposes.

¤ The inhibitory basis of will-power

¤ The historical role of inhibition in psychological theory

¤ Voluntary and involuntary attention

¤ Mental fatigue and the debilitating effects of attentional deficits

¤ The commonalities between mental fatigue, ADHD, and prefrontal cortex injuries.

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Pathways in the Mind: Solving Problems





¤ "In the Head" vs "In the World" problem solving.



¤ Variation and selection in problem solving and natural selection.



¤ The power of models -- problem-solving as off-line trial-and-error.



¤ Potential dangers and drawbacks of mental models.



¤ An incremental approach to off-line problem-solving



¤ Cognitive maps and problem spaces



¤ Memory retrieval as problem-solving



¤ The apparent weakness of human problem-space searching capabilities



¤ Perception, framing, analogies, and generic structures



¤ The effects of framing on some real world social problems





Advantages and disadvantages of knowing a whole lot: On Expertise

 Why the following isn't true: The more we learn the more there is to think about

– and the longer everything takes?

 How being able to operate economically and efficiently plays a big role in

expertise

 One tradeoff of this is the inarticulable nature of expertise

 Content-specific nature of expertise

 Differences between experts and novices

 Ads and disads





Tradeoffs



What is lost What is gained

Flexibility Competence

Information Speed, efficiency, compactness, economy

Articulability Speed, efficiency, compactness, economy

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Keeping on track: Temptations and other hazards





¤ The modern dilemma part 1 -- society imposes many tasks that are not inherently

compelling and for which the human mind is not ideally suited.



¤ The modern dilemma part 2 -- societies offer a vast, readily accessible supply of

potential hazards and temptations that are inherently fascinating (and, in fact, often have

been intentionally designed to be so).



¤ Direct and indirect effects of temptations



¤ A taxonomy of artificial supernormal stimuli: sneaky, simple, and synthetic



¤ The threat of a limitless supply of fascinating, worthy, valuable, intelligent stuff



¤ The dangers of bigger-than-life virtual experiences.



¤ Serial-killers, terrorists, fist-fights, gang-wars, car-chases, heiresses, tycoons,

generals, champion athletes, mansions, mega-yachts, prostitutes, mafia dons, government

conspiracies, flawless skin, perfectly-toned bodies, hurricanes, tornadoes, floods, and

fires



¤ Biases: adaptation levels, misplaced priorities, and unrealistic beliefs



¤ Implicit associations



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