20 Apr 2010
Word: Low Latent Inhibition
“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.”
Most people are able to ignore the constant stream of incoming stimuli, but this capability is reduced in those with low latent inhibition. It is hypothesized that a low level of latent inhibition can cause either psychosis or a high level of creative achievement[3] or both, which is usually dependent on the subject’s intelligence.[4][2] Those of above average intelligence are thought to be capable of processing this stream effectively, enabling their creativity. 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.[5]
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.
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.[citation needed] In contrast to certain popular depictions, low latent inhibition is not a mental disorder but an observed personality trait, and a description of how an individual absorbs and assimilates data or stimuli. Furthermore, it does not necessarily lead to mental disorder or creative achievement—this is, like many other factors of life, a case of environmental and predispositional influences, whether these be positive (e.g., education) or negative (e.g., abuse) in nature.
“Throughout our daily lives we experience an influx of emotions, sensations, and sounds,” he writes. “If we had to consciously decide at all times what to ignore and what to pay attention to, we would quickly become overstimulated.
“This ability to screen things out of awareness that were previously tagged as irrelevant is called latent inhibition. Latent inhibition has a strong biological basis and operates automatically to filter out information.
“Those high in latent inhibition are very good at this inhibition. Those with a reduced latent inhibition have a difficult time with this form of inhibition. Reduced latent inhibition has been associated with schizophrenia as well as a predisposition to psychosis.”
Peterson et al. (2002) argued that individual differences in a tendency toward exploratory behavior and cognition may be related to the activity of the mesolimbic dopamine system and predispose an individual to perceive even preexposed stimuli as interesting and novel, resulting in low LI. Moreover, under stressful or novel conditions, the dopamine system in these individuals will become more activated and the individual will instigate exploratory behavior. Under such conditions, decreased LI could help the individual by allowing him or her more options for reconsideration and thereby more ways to resolve the incongruity. It could also be disadvantageous in that the stressed individual risks becoming overwhelmed with possibilities. Research has shown that the combination of high IQ and reduced LI predicts creative achievement (Carson et al., 2003). Therefore, the individual predisposed to schizophrenia may suffer from an influx of experiential sensations and possess insufficient executive functioning to cope with the influx, whereas the healthy individual low in LI and open to experience (particularly an openness and faith in his or her gut feelings) may be better able to use the information effectively while not becoming overwhelmed or stressed out by the incongruity of the situation. Clearly, further research will need to investigate these ideas, but an understanding of the biological basis of individual differences in different forms of implicit processing and their relationship to openness to experience and intuition will surely increase our understanding of how certain individuals attain the highest levels of creative accomplishment.
“After all, decreased LI may make an individual more likely to see connections that others may not notice. Prominent psychologists such as Hans Eysenck and Colin Martindale have argued for the importance of disinhibition for creative thought.
Erika Harris says:As an HSP, I identify with having decreased LI. And I imagine most HSPs would. Even when we would very much like to filter out excess stimuli from our environments, our nervous systems keep feeding us the data and sensory inputs… regardless if we feel quite full. So, it seems since we don’t have access to *inner* LI, we place special emphasis on *outer* LI — we create sanctuaries for ourselves… quiet spaces… regenerative nooks where we can give our neurons a much needed break.
This was a very thought-provoking article. Thank you for it, and all of the treasures here.
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.
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.
- chronic stress paradigm used was that of social defeat (cohabitation with a socially dominant conspecific). 10 days of this social defeat were administered. this typically leads to social avoidance behaviors and these behaviors are correlated with other depressive phenotypes.
- after 10 days when social avoidance (time interacting with a potential friendly con-specific) was measured it was found that about half the mice exhibited social avoidance and were sensitive to the stress; the rest of the half were ‘resilient’ and did not differ from control mice (not exposed to chronic social defeat) in their social avoidance.
- all mice, both resilient and sensitive , showed decreased proliferation in subgranular zone (SGZ) for new cells immediately after stress exposure. This effect disappeared / normalised after 24 hrs.
- Cell survival for cells created before stress exposure was not affected by stress exposure.
- cell survival for neurons created 1 day after stress exposure was enhanced selectively for those mice that were susceptible or sensitive to stress, but was not enhanced for the resilient mice or the mice taken as a whole.
- when the mice were irradiated, before stress exposure, to prevent neurogenesis, then the social avoidance behavior, even in susceptible mice disappeared. It is thus evident that social avoidance is mediated by increased neurogenesis post-stress exposure in the susceptibel mice.
The only hiccup I see in the whole scheme of things is the effect of anti-depressants on neurogenesis and my earlier theorizing that cells may die under repetitive stress and reduced or absent neurogenisis would be a prime factor in depression. However, the relation between neurogenesis and stress will be , I am sure, complex and needs to be settled empirically, rather than theoretically. However one thing is clear, neurogenesis has a rpime role to play in depression , mediated perhaps by, chronic stress exposure and genetic diatheisis (orchid-dandelion effect).
