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Unconscious Thought Processes

Unconscious thought processes have been discussed since the time of Aristotle. The topic periodically becomes popular with scholars and the general public.

In a book titled The Unconscious Before Freud (1966) L. L. Whyte pointed out that speculation about the unconscious mind was very fashionable in Europe during the 1830s, and in 1840 there was a best seller titled The Psychology of the Unconscious.

Another surge of speculation about the nature and function of uncon­scious processes occurred around 1900-1920, largely outside academic psychology, stimulated by psychiatrists such as Sigmund Freud and Carl Jung.

Yet another surge of interest occurred from the 1980s to the present. This time, psychologists had better tools than before. They could see hidden activity on brain scans, and they could infer things about information processing that occurred outside the focus of attention.

In one noticeable change, present-day scientists seldom refer to "the" unconscious mind. Most scientists believe there are many unconscious processes. It is more accurate to use the plural form unconscious processes rather than the unconscious.

What did Whyte point out in his book? What is a change in the way present day scientists talk about "the unconscious"?

Uleman and Bargh (1989) found that researchers used at least five different definitions of unconscious mental processes:

1. Mental activity is unconscious if people are unaware of it. For example, you might tap your toe to music without realizing it.

2. Something is unconscious if it happens without effort. For example, in speaking, you retrieve words in your everyday vocabulary quickly and smoothly, without conscious effort.

3. An unconscious action is one that is unintended. For example, you might accidentally call one person by another person's name.

4. An unconscious mental process is autonomous (runs by itself, without conscious attention). For example, you set your alarm to 7 a.m. and find yourself waking up at 6:59 a.m.

5. A behavior is unconscious if it resists conscious control, for example, a person might not be able to stop saying "um" or "you know" despite trying.

These are overlapping categories. Of the five categories, the fourth (being autonomous) seems broadest. An autonomous process is an automatic or self-acting process. All five definitions involve autonomous processes.

What is the most general of the five definitions?

Influenced by the legacy of behaviorism, many cognitive psychologists of the mid-20th Century were still reluctant to use the words conscious or uncon­scious. The word automatic (the opposite of conscious) does not seem to carry the same stigma.

Experimenters commonly used the term automatic in place of unconscious. In those publi­cations, non-automatic serves as a substitute for conscious.

Similarly, the term attention became a substitute for consciousness in psychology journals. The word intention, referring to conscious efforts to alter mental events, also creept back into scholarly discourse.

See, for example, the Suzuki and Peterson (2000) study reported in Chapter 7. They studied the ability of people to intentionally prevent changes of perspective in a famous illusion, the Necker Cube. In this case, intention seems to be equivalent to the willful application of executive control, what some people call willpower.

Unconscious Learning

Psychologists have evidence that learning starts as unconscious activity. This sounds like a contra­diction of Mandler's idea that conscious control is used when learning something new, but not if an unconscious phase of learning occurs before the phase described by Mandler.

Mandler saw a role for conscious attention in grasping to-be-learned material for the first time. A pre-cons­cious phase may occur before a person can grasp any pattern consciously. This is called implicit learning (whether or not it is followed by conscious awareness).

Add implicit, the opposite of explicit, to the list of modern euphemisms for unconscious, along with automatic and non-attentional. Implicit learning is commonly described as tacit (unspoken) so that gives us a fourth synonym on the list.

This may seem humorous: so many ways of saying "unconscious" without saying it. For years, the public associated "the unconscious" with Freud. Experimental psychologists want to avoid association with that, but they do recognize a powerful role for unconscious processes in cognition.

An example of unconscious learning comes from the work of Arthur Reber, who studied implicit learning for many years. In a 1967 experiment, Reber showed subjects a set of letter strings (such as TSXS, TSSXXVPS, and PVV) generated using a hidden rule.

Soon the subjects were able to judge whether new letter strings fit the rule. They could do this despite being unable to specify the rule.

This is what people commonly call intuition: knowledge from an unknown source. The subjects knew whether a new letter string fit the rule, but they did not know how they knew.

What is implicit learning? What was Reber's classic experiment on implicit learning?

Reber carried out many such demon­strations. He used different procedures to rule out alternative explanations. In the end, he concluded that learning typically begins with unconscious processes.

Brain-scanning research bears this out. For example, the anterior cingulate gyrus, an area crucial to executive control ("willpower") and planned activity, shows different responses to wins and losses in gambling before a person is conscious of them (Gehring & Wiloughby, 2002).

In what sense does unconscious learning mimic our species history, in Reber's view?

Reber (1993) argued that each individual act of learning mimics our species history. "Conscious­ness is a late arrival on the evolutionary scene," he pointed out.

"Sophisticated unconscious perceptual and cognitive functions preceded its emergence by a considerable margin." Similarly, in the individual act of learning, consciousness is a late arrival, following unconscious perceptual and cognitive functions that first detect a pattern.

Here is a typical experiment that supports Reber's theory of implicit learning. It comes from Dr. Pawel Lewicki. He had volunteers try to predict where an X would appear on a computer screen, selecting one of four quadrants.

The subjects pushed a button corresponding to the quarter of the screen where they predicted the X would appear next. The X followed a pattern determined by 10 simul­taneous rules.

Lewicki offered $100 to anybody who could report the rules (after the experi­ment was over) but nobody could specify them. However, the volunteers became more and more successful with their predictions as the experiment went on.

They sensed the pattern, whatever it was. Their predictions became more accurate until Lewicki suspended the rules and moved the X randomly, then their performance dropped to pre-learning levels again (Goleman, 1992).

How did a researcher study implicit learning with an X appearing in various parts of a computer screen?

At some point a person may grasp a pattern, making it conscious. This process can be traced in brain scans.

Pascual-Leone, Grafman, and Hallett (1994) used a technique called transcranial magnetic stimulation (TMS) to study this. They used a motor (movement) task and looked for changes in the motor cortex as subjects practiced.

The transition from unconscious know­ledge to conscious knowledge and finally automaticity showed up as changes in the brain scans. Initially, while subjects tried to figure out the task, areas of the cortex showing activation grew larger.

The enlargement of these "output maps" increased until subjects achieved explicit knowledge of the task, becoming conscious of the pattern. After this, their reactions became gradually more automatic with practice. The areas of brain activity shrank so that, when the task was fully learned and automatic, only a small area of cortex was active.

How did brain scans change as people practiced a simple motor skill? What similar pattern was observed when subjects were asked to respond to nouns with associated verbs?

Raichle (1994) reported a very similar finding. Subjects presented with nouns had to respond with an associated verb, as rapidly as possible. For example, given baseball the subject might respond hit. Given the noun money the subject might respond buy.

Nouns were presented every second and a half. At first, the subjects hesitated while they thought of an appropriate verb. After less than 15 minutes of practice, the task became easier (they caught on).

After that, areas of activity in the brain shrank. Finally the brain responses resembled the patterns produced by reading single words, an automatic process for fluent readers. It involved only a small area of brain tissue.

The pattern revealed by this research seems sensible. Initially, as the brain grapples with a new problem, large areas are involved. Many neurons have a chance to volunteer for inclusion in the problem-solving activity.

Some of the neurons prove necessary for solving the task, others do not. Once the problem is solved, or the task becomes familiar, a smaller group of neurons–those most essential to the activity–takes over responsi­bility.

After this, automaticity is possible. The rest of the mind can wander to some­thing else, while skilled perform­ance continues.


Gehring, W. J. & Willoughby, A. R. (2002) The medial frontal cortex and the rapid processing of monetary gains and losses. Science, 22, 2279-82.

Goleman, D. (1992, June 23). Your unconscious mind may be smarter than you. The New York Times, pp. 5, 11.

Pascual-Leone, A., Grafman, J., & Hallett, M. (1994). Modulation of cortical motor output maps during development of implicit and explicit knowledge. Science, 263, 1287-1289.

Raichle, M. E. (1994). Images of the mind: Studies with modern imaging techniques. Annual Review of Psychology, 45, 333-356.

Reber, A. S. (1967) Implicit learning of artificial grammars. Journal of Verbal Learning and Verbal Behavior, 6, 855.

Suzuki, S. & Peterson, M. A. (2000). Multiplicative effects of intention on the perception of bistable apparent motion. Psychological Science, 11, 202-209.

Uleman, J. S. & Bargh, J. A. (Eds). (1989). Unintended thought. New York: Guilford Press.

Whyte, L. L. (1960). The Unconscious Before Freud. New York: Basic Books.

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