The P.S.I.A. comprise twelve scales, two of which, Introverted and Neurotic, are well known from other tests and considered fundamental personality factors, while the remaining ones are experimental and subject to research. There are also two factors called Deviance and Ethics, which are derived from the twelve basic scales by combining scales that intercorrelate well (tend to go together, form a cluster). And attempts are being made to use some of the scales to obtain measures of conscientiousness and associative horizon, two of the components of creativity and genius.
The below image gives an impression of the Deviance dimension; There is increasing Deviance from the bottom to the top of the image.
The distribution of the P.S.I.A. items over the eleven scales other than Extreme is based on item analysis; Each item counts toward the scale with which it has its highest correlation, while a small number of inconclusive items is not used for any of these eleven. The Extreme scale uses all of the items. This statistical method is needed as test items often behave in ways different from what one would intuitively expect. This is so because they work on a subconscious level. There is no question of that one can ask "Are you orderly?" and blindly count that answer toward the Orderly scale. Internal test statistics reveal to what scale an item belongs, and that scale's correlations with outside criteria reveal what the scale is measuring.
A brief discussion the scales follows. Statistics based on a large number of candidates can be found on the page with statistical reports, where each scale has its own report. Also, in Your profile based on Cooijmans tests suggestions are given for how to interpret some of the scales in terms of components of creativity.
This is the dimension Introversion/Extraversion. A high score basically means one is happier alone than with others, a low score the opposite. For high achievement in most fields, a relatively high degree of Introversion is needed to be able to do the solitary work required. There are of course exceptions, in particular certain performing arts like singing, dancing and acting, where Extraversion is required. Extreme Introversion is characteristic of Asperger Syndrome and Schizoid Personality.
The biological cause behind this scale is thought to lie in "cortical arousal". Introverts are chronically overaroused and anxious and therefore tend to stay away from strong stimuli, while Extraverts are chronically underaroused and bored, and therefore seek outside stimulant.
Introversion/Extraversion is the only dimension of personality that is already observable with some reliability in the first year of life, where it is described as inhibited versus uninhibited behaviour. Other personality features only become apparent after about the age of six.
This is the dimension Stability/Neuroticism. A low score means you have high tolerance for stress and stay calm under pressure. A high score means you get nervous, anxious and so on even under light stress; You are "neurotic". High Neuroticism makes you vulnerable to affective disorders (depression, bipolar disorder). When it comes to high achievement, neurotics tend toward art, while stable persons tend toward science.
The biological cause behind this scale lies in activation thresholds of the sympathetic nervous system. When activated, this gets you in a fight-or-flight state; prepared for action, while the digestive system comes to a standstill and eating becomes impossible. Neurotics have a low activation threshold, while stable persons have a high threshold.
This is a revised version of the GAIA Asperger questionnaire. A high Aspergoid score disposes for both affective and psychotic disorders, as well as for creativity and, rarely, criminal psychopathy.
The biological background of this scale is not known, but a somewhat informed guess is that it is related to both prenatal testosterone (Higher testosterone level gives greater risk of Asperger) and the dopamine/serotonin balance (higher ratio gives greater risk). This is speculative however.
This is the range Cold/Empathic. A high score means you have little consideration for the feelings of others, a low score the opposite. A very high score may dispose for crime.
This is the inclination to be cruel, which certainly disposes for crime and psychopathy. This scale appears to be the opposite end of True, or at least has a significant negative correlation with it.
This scale deals with strong sense of justice and desire to punish criminals. High scores on Just also indicate lack of empathy, so that this scale is to some extent an upward extension of Cold.
This ranges from system, order, coherence and conscientiousness (high scores) to being disorganized and lax (low). This too may be an upward extension of Cold. The dimension systemizing/empathizing has been mentioned by S. Baron-Cohen in relation to autism (autism being the systemizing side).
This deals with unusual, unshared, unbelieved (by others) perceptions and experiences.
This is the dimension Truthful/Lying. This scale appears to be the opposite end of Cruel, or at least has a significant negative correlation with it.
This is one's inclination to behave in a way that may displease or endanger others and oneself, and display disregard for law, society and people.
This is one's disinclination to believe in various paranormal, religious, spiritual and occult matters.
This is one's inclination to give extreme responses on this test; that is, to respond with 0 or 4 rather than with 1, 2 or 3.
Two factors have been derived from the twelve scales after studying their intercorrelations. Factors are groups of scales that cluster together. Below a brief description and some statistics.
The Deviance factor score is a standardized average based on the scales Aspergoid, Introverted, Rare and Extreme.
The Ethics factor score is a standardized average based on the scales True and Cruel (the latter reversed).