Trials‐to‐criterion latent inhibition in humans as a function of stimulus pre‐exposure and positive‐schizotypy

Abstract

Latent inhibition (LI) is a phenomenon during which non-reinforced pre-exposure to a stimulus retards later learning of associations with that same stimulus. It has been suggested that LI is a positive function of the amount of stimulus pre-exposure (PE) and that with very small amounts of PE, facilitation rather than inhibition will occur-particularly in high positive-schizotypes. Although LI has been demonstrated as a function of the amount of pre-exposure in animals, human findings have not proved to be so uniform or consistent. The primary objective of the present study was to establish LI as a function of numbers of pre-exposure on visual and auditory trials-to-criterion tasks, with a secondary objective to establish latent facilitation (LF) with very low numbers of pre-exposure in high positive-schizotypes. Results revealed a uniform pattern of learning across pre-exposure conditions, including latent facilitation, on the visual, but not the auditory task. LF was also observed in the high, but not low, scorers in positive-schizotypy with very low numbers of pre-exposure on the visual task.

Intelligence and Cognitive Control

“…The subject had to learn that a change in the numerical value of a counter was associated with the presence of the previously irrelevant PE stimulus. The PE group reached the learning criterion more slowly than the NPE group, thereby demonstrating the LI effect (for similar results with between-group designs, see e.g., Burch, Hemsley, & Joseph, 2004;Gray, Fernandez, Williams, Ruddle, & Snowden, 2002; and with withinsubject designs, e.g., De La Casa & Lubow, 2001;Gray, Snowden, Peoples, Hemsley, & Gray, 2003;Swerdlow et al, 2003).…”

“…Given the above rationale, the study of the relationship between LI and schizophrenia has been extended to healthy populations that are differentiated on the basis of schizotypy scores, usually by median-split (e.g., Baruch, Hemsley, & Gray, 1988b;Braunstein-Bercovitz & Lubow, 1998) but sometimes also by subscale scores (e.g., Burch et al, 2004;Gray et al, 2002).…”

“…The evidence that relatively few stimulus preexposures facilitate subsequent learning, even when contexts are constant, comes primarily from animal studies (e.g., Bennett, Tremain, & Mackintosh, 1996;Hoffmann & Spear, 1989;Prados, 2000). However, one experiment suggests a similar effect for humans (Burch et al, 2004).…”

Selective Information Processing Advantages in Creative Cognition as a Function of Schizotypy

“…The selective advantage of the high schizotypy group on the constraints of examples task, but not the conceptual expansion or creative imagery tasks, can perhaps be interpreted in light of findings in the neuropsychological literature that suggest not only inadequate cognitive and motor inhibition in association with schizotypy (e.g., Burch, Hemsley, & Joseph, 2004;Holahan & O'Driscoll, 2005;Lubow & De la Casa, 2002;O'Driscoll, Lenzenweger, & Holzman, 1998) but also inadequacies on facets of executive function such as working memory (e.g., Lenzenweger & Gold, 2000;Park & McTigue, 1997) and set-shifting (Gooding, Kwapil, & Tallent, 1999;Lenzenweger & Korfine, 1994). The constraints of examples task can be likened to the functional opposite of a working memory task where task relevant information needs to be actively maintained in order to reach a goal successfully.…”

“…The rationale commonly employed to explain enhanced creative abilities in schizotypy is the propensity for poorer cognitive inhibitory control in high schizotypy subjects relative to low schizotypy subjects, a finding that has received some support using different methods (e.g., Beech & Claridge, 1987;Burch, Hemsley, & Joseph, 2004;Lubow & De la Casa, 2002). This reduced ability to adequately inhibit irrelevant information is held to result in the influx of more irrelevant or distantly associated concepts into the information processing stream and therefore, by extension, the heightened potential to form unusual or unique conceptual associations.…”