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Latent inhibition

Latent inhibition is a process by which exposure to a stimulus of little or no consequence prevents conditioned associations with that stimulus being formed. The ability to disregard or even inhibit formation of memory, by preventing associative learning of observed stimuli, is an automatic response and is thought to prevent information overload. Latent inhibition is observed in many species, and is believed to be an integral part of the observation/learning process, to allow the self to interact successfully in a social environment.

Contrary to certain popular culture descriptions, low latent inhibition is not a mental disorder but an observed personality trait, and a description of how an individual absorbs and assimilates information or stimuli. It may or may not lead to mental disorder or creative genius—this is, like many other factors of life, a case of environment (positive stimuli e.g. education or negative stimuli e.g. abuse) and an individual's predisposition.

Low latent inhibition

Most people are able to shut out the constant stream of incoming stimuli, but those with low latent inhibition cannot. It is hypothesized that a low level of latent inhibition can cause either psychosis, a high level of creativity or both, which is usually dependent on the subject's intelligence. Those of above average intelligence are thought to be capable of processing this stream effectively, an ability that greatly aids their creativity and ability to recall trivial events in incredible detail and which categorizes them as almost creative geniuses. Those with less than average intelligence, on the other hand, are less able to cope, and so as a result are more likely to suffer from mental illness. Still, very many individuals who have a high level of intelligence and low latent inhibition suffer from mental differences.

High levels of the neurotransmitter dopamine (or its agonists) in the brain are thought to lower latent inhibition. Certain dysfunctions of the neurotransmitters glutamate, serotonin and acetylcholine have also been implicated, and the glutamate hypothesis of schizophrenia is increasingly being seen as an alternative to the classic dopamine hypothesis of schizophrenia.

In recent years, low latent inhibition is being looked at as less of a mental disorder; in the past it was often confused with schizophrenia, attention deficit disorder, bipolar disorder, and even depression, and almost all cases of misdiagnoses have been known to lead to over-medicated individuals.[citation needed] In some cases, these individuals have had adverse reactions to the intended medicines.

Low Latent Inhibition Plus High Intelligence Leads To High Creativity?

Jordan Peterson of the University of Toronto and colleages at Harvard University have found that decreased latent inhibition of environmental stimuli appears to correlate with greater creativity among people with high IQ. (same press release available here and here)

The study in the September issue of the Journal of Personality and Social Psychology says the brains of creative people appear to be more open to incoming stimuli from the surrounding environment. Other people's brains might shut out this same information through a process called "latent inhibition" - defined as an animal's unconscious capacity to ignore stimuli that experience has shown are irrelevant to its needs. Through psychological testing, the researchers showed that creative individuals are much more likely to have low levels of latent inhibition.

"This means that creative individuals remain in contact with the extra information constantly streaming in from the environment," says co-author and U of T psychology professor Jordan Peterson. "The normal person classifies an object, and then forgets about it, even though that object is much more complex and interesting than he or she thinks. The creative person, by contrast, is always open to new possibilities."

Previously, scientists have associated failure to screen out stimuli with psychosis. However, Peterson and his co-researchers - lead author and psychology lecturer Shelley Carson of Harvard University's Faculty of Arts and Sciences and Harvard PhD candidate Daniel Higgins - hypothesized that it might also contribute to original thinking, especially when combined with high IQ. They administered tests of latent inhibition to Harvard undergraduates. Those classified as eminent creative achievers - participants under age 21 who reported unusually high scores in a single area of creative achievement - were seven times more likely to have low latent inhibition scores.

The authors hypothesize that latent inhibition may be positive when combined with high intelligence and good working memory - the capacity to think about many things at once - but negative otherwise. Peterson states: "If you are open to new information, new ideas, you better be able to intelligently and carefully edit and choose. If you have 50 ideas, only two or three are likely to be good. You have to be able to discriminate or you'll get swamped."

"Scientists have wondered for a long time why madness and creativity seem linked," says Carson. "It appears likely that low levels of latent inhibition and exceptional flexibility in thought might predispose to mental illness under some conditions and to creative accomplishment under others."

A less able mind has a greater need to be able to filter out and ignore stimuli. A less intelligent person with a low level of latent inhibition for filtering out familiar stimuli may well sink into mental illness as a result. But a smarter mind can handle the effects of taking note of a larger number of stimuli and even find interesting and useful patterns by continually processing a larger quantity of familiar information.

You can find the original paper here: Decreased Latent Inhibition Is Associated With Increased Creative Achievement in High-Functioning Individuals (PDF format)

The central idea underlying our research program is therefore that individuals characterized by increased plasticity (extraversion and openness)retain higher post-exposure access to the range of complex possibilities laying dormant in so-called ‘‘familiar ’’environments.This heightened access is the subjective concomitant of decreased latent inhibition,which allows the plastic person increased incentive-reward-tagged appreciation for hidden or latent information (Peterson,1999). Such decreases in LI may have pathological consequences,as in the case of schizophrenia or its associated conditions (perhaps in individuals whose higher-order cognitive processes are also impaired,and who thus become involuntarily ‘‘flooded ’’by an excess of a ffectively tagged infor- mation),or may constitute a precondition for creative thinking (in individuals who have the cognitive resources to ‘‘edit ’’or otherwise constrain (Stokes,2001)their broader range of mean- ingful experience).

Note from the text of the full paper that stress causes the release of the hormone corticosterone which lowers latent inhibition. In a nutshell, when an organism runs into problems that cause stress the resulting release of stress hormones causes the mind to shift into a state where it will examine factors in the environment that it normally ignores. This allows the organism to look for solutions to the stress-causing problem that would be ignored in normal and less stressed circumstances.

So perhaps we could hypothesize something like this:under stressful conditions,or in person-ality configurations characterized by increased novelty-sensitivity,approach behavior,and DA activity, decreased LI is associated with increased permeability and flexibility of functional cog- nitive and perceptual category [see Barsalou (1983)for a discussion of such categories ].Imagine a situation where current plans are not producing desired outcomes —a situation where current categories of perception and cognition are in error, from the pragmatic perspective. Something anomalous or novel emerges as a consequence (Peterson,1999), and drives exploratory behavior. Stress or trait-dependent decreased LI, under such circumstances, could produce increased signal (as well as noise), with regards to the erroneous pattern of behavior and the anomaly that it produced. This might offer the organism, currently enmeshed in the consequences of mistaken presuppositions, the possibility of gathering new information, where nothing but categorical certainty once existed. Decreased LI might therefore be regarded as advantageous, in that it allows for the perception of more unlikely, radical and numerous options for reconsideration, but disadvantageous in that the stressed or approach-oriented person risks ‘‘drowning in possibility,’’ to use Kierkegaard ’s phrase.

One can easily see how this response could have been selected for evolutionarily. At the same time, one can also see how chronic stress could lead a person to fall into a state of confusion as a sustained large flood of stimuli could overwhelm the brain by giving it too much to think about and make a person unable to clearly see solutions that will relieve the feeling of stress.