Positive Schizotypy Increases the Acceptance of Unpresented Materials in False Memory Tasks in Non-clinical Individuals

Abstract

Enhanced spreading of semantic activation has been hypothesized to underlie some of the most significant symptoms of schizotypal personality, like thought disorder, odd speech, delusion, or magical thinking. We applied the Deese/Roediger-McDermott false memory task to the study of semantic activation in a group of 123 nonclinical individuals varying in the three dimensions of schizotypal personality: positive, negative and disorganized schizotypy. In the study phase, we presented them with lists composed of words semantically associated to unpresented critical words. Then, they responded to a recognition questionnaire including previously presented words and critical unpresented lures, as well as weakly related and unrelated unpresented lures. Participants rated their confidence in recognizing each word. They also filled in a standardized schizotypal personality questionnaire. Confirming the false memory effect, recognition ratings provided in response to critical words were higher than those produced for both weakly related and unrelated items. Crucially, scores in the positive dimension increased recognition percentages and confidence ratings for weakly related and unrelated lures. This study indicates that high levels of positive schizotypy might influence the tendency to accept false memories of unrelated unpresented material.

Amplified Mnemonic Discrimination and Attenuated Generalization Are Associated with Positive Schizotypy

“…Similarly, inconsistent results have emerged in healthy participants who exhibit schizotypal traits (Rodríguez-Ferreiro et al, 2020). Some studies found a positive relation between false memories and positive schizotypy.…”

“…An enhanced pattern completion may imply a diffuse spreading of semantic activation which could cause over-activation of loosely associated concepts or connecting unrelated events (i.e. magical ideation) (Rodríguez-Ferreiro et al, 2020).…”

“…Moreover, patients with schizophrenia are also hypothesized to possess a more liberal acceptance level. This implies that being unaware of their reduced metacognitive awareness, they may require only little evidence before arriving at strong conclusions (Rodríguez-Ferreiro et al, 2020 andWoodward et al, 2008). Liberal acceptance level can be considered a core underlying feature of delusions and aberrant salience in schizophrenia (Woodward et al, 2008).…”

Semantic priming and schizotypal personality: reassessing the link between thought disorder and enhanced spreading of semantic activation

“…Crucially, in accordance with previous observations with schizophrenia patients (see Pomarol-Clotet et al, 2008 ), some authors argue that this mechanism could also underlie the presence of atypical speech patterns or ideas of reference associating unrelated events in schizotypal individuals ( Mohr et al, 2001 ; Pizzagalli, Lehmann & Brugger, 2001 ). Nevertheless, other studies have failed to obtain significant associations between the originality of fluency responses ( Hori et al, 2008 ; Rodríguez-Ferreiro & Aguilera, 2019 ) or semantic-based false memory rates ( Corlett et al, 2009 ; Kanemoto et al, 2013 ; Rodríguez-Ferreiro, Aguilera & Davies, 2020 ) and differences on schizotypal traits, so the reliability of these observations is unclear.…”

News and Commercials: Binding Deficits for Complex Information in Schizophrenia

“…It was reported that while all schizophrenia patients have fewer correct recognitions compared to healthy controls, acutely delusional patients have twice as many false recognitions as healthy controls and schizophrenia patients without current delusions ( 7 ). Proneness to delusions ( 7 ) and positive schizotypy ( 8 , 9 ) has been linked to false memories even in non-clinical populations. Similarly, decreased hit rates in recognition task, has been associated with negative schizophrenia symptoms ( 10 ).…”