Linguistic and neurocognitive correlates of probabilistic classification learning in schizophrenia

Abstract

Individuals with schizophrenia demonstrate impaired implicit learning on cognitively complex tasks and preserved implicit motor learning. However, little is known about how implicit learning may be related to other linguistic and cognitive variables, including development of complex language including comprehension and syntax. This study explored the relationship between probabilistic classification learning, a type of implicit learning style, and linguistic and cognitive skills in schizophrenia. This was done by examining how schizophrenia patients perform on the Weather Prediction Task (WPT) relative to controls, particularly during a dual-task interference condition that assesses task automaticity. Individuals with schizophrenia ( N = 34) demonstrated depressed cognitive functioning relative to the controls ( N = 18) across nearly all cognitive functions. On the Weather Prediction Task, the schizophrenia group performed less accurately than the control group in later blocks and had a relatively flat learning curve. A significant Group X Block effect when controlling for age and sex suggested differential learning throughout the task. A subgroup of patients did not develop automaticity during the repeated blocks of trials. For those patients who did not develop automaticity over the course of the WPT, linguistic and cognitive skills were strongly correlated with their Block 1 performance. For patients who developed automaticity, overall neurocognitive ability was correlated with their ultimate level of performance on the WPT but not with their Block 1 performance. That language was related to differential learning emphasizes the role of explicit, verbal processes on making initial rapid improvement on the WPT.

What Is the Weather Prediction Task Good for? A New Analysis of Learning Strategies Reveals How Young Adults Solve the Task

“…Although several studies have questioned the view that the WPT implicates primarily non-declarative learning and memory processes ( Knowlton et al, 1996a ; Poldrack et al, 2001 ; Gluck et al, 2002 ; Hopkins et al, 2004 ; Foerde et al, 2006 , 2007 ; Lagnado et al, 2006 ; Meeter et al, 2006 ; Newell et al, 2007 ; Price, 2009 ; Li et al, 2016 ), numerous studies evaluating the learning capacities of various clinical populations were conceived with the notion that the WPT assesses striatum-dependent or procedural learning. Indeed, the WPT or the Ice Cream Task, a modified version of the WPT in which participants must predict the flavor of ice cream preferred by a cartoon figure based on the different accessories worn by that figure ( Shohamy et al, 2004a ), have been extensively used in clinical populations to evaluate the behavioral consequences of known or presumed structural or functional basal ganglia deficiencies: for example in schizophrenia ( Keri et al, 2000 ; Weickert et al, 2002 ; Foerde et al, 2008 ; Horan et al, 2008 ; Gomar et al, 2011 ; Karcher et al, 2019 ; Fernandez et al, 2021 ), Tourette syndrome ( Keri et al, 2002 ; Marsh et al, 2004 ), bulimia nervosa ( Labouliere et al, 2016 ), attention-deficit hyperactivity disorder ( Gabay and Goldfarb, 2017 ), Parkinson and Huntington diseases ( Knowlton et al, 1996a , b ; Shohamy et al, 2004a , b ), and children with acquired or developmental basal ganglia pathology ( Mayor-Dubois et al, 2010 ). Researchers have also used these tasks to assess memory capacities in individuals with neurodevelopmental disorders thought to be characterized by some procedural memory deficits, such as autism ( Brown et al, 2010 ; Obeid et al, 2016 ), obsessive–compulsive disorder ( Exner et al, 2014 ; Kelmendi et al, 2016 ; Hansmeier et al, 2018 ), specific language impairment ( Kemeny and Lukacs, 2010 ; Mayor-Dubois et al, 2014 ; Obeid et al, 2016 ), or developmental dyslexia ( Gabay et al, 2015 ).…”

“…In sum, despite the fact that several studies have shown that the WPT does not necessarily assess striatal-dependent implicit memory in healthy young adults ( Knowlton et al, 1996a ; Poldrack et al, 2001 ; Gluck et al, 2002 ; Hopkins et al, 2004 ; Foerde et al, 2006 , 2007 ; Lagnado et al, 2006 ; Meeter et al, 2006 ; Newell et al, 2007 ; Price, 2009 ; Li et al, 2016 ), this task is still used to determine whether specific populations exhibit impairments of this memory system ( Knowlton et al, 1996b ; Keri et al, 2000 , 2002 ; Weickert et al, 2002 ; Marsh et al, 2004 ; Shohamy et al, 2004a , b ; Foerde et al, 2008 ; Horan et al, 2008 ; Brown et al, 2010 ; Kemeny and Lukacs, 2010 ; Mayor-Dubois et al, 2010 , 2014 ; Gomar et al, 2011 ; Exner et al, 2014 ; Gabay et al, 2015 ; Kelmendi et al, 2016 ; Labouliere et al, 2016 ; Obeid et al, 2016 ; Hansmeier et al, 2018 ; Karcher et al, 2019 ; Fernandez et al, 2021 ). Moreover, knowing that different learning strategies can lead to above chance performance in the WPT, it is fundamental to determine how participants solve the task ( Ashby and Maddox, 2005 ).…”

Impaired implicit learning in adults with anorexia nervosa

“…The WPT (Knowlton et al, 1994) is a probabilistic learning task assessing procedural learning, which has been successfully used in a variety of neuropsychiatric diseases, ranging from bulimia nervosa (Labouliere et al, 2016), major depression (Mörkl et al, 2016), and schizophrenia (Fernandez et al, 2021; Gomar et al, 2011; Karcher et al, 2019) to attention‐deficit hyperactivity disorder (ADHD; Gabay & Goldfarb, 2017). The procedure of the WPT is described in detail in Supporting Information File S1.…”

When and how do children solve the Weather Prediction Task?

“…Importantly, participants are not explicitly informed about the probabilistic nature of the task. Due to the probabilistic nature of the WPT, participants were originally considered to gradually acquire implicit knowledge about the cue-outcome associations across successive trials via striatum-dependent learning processes (e.g., Brown et al, 2010;Fernandez et al, 2021;Knowlton et al, 1994; but see Lagnado et al, 2006). Behavioral and neuroimaging studies, however, have provided evidence that the WPT implicates both hippocampus-dependent declarative processes and striatumdependent non-declarative processes (Foerde et al, 2006(Foerde et al, , 2007Gluck et al, 2002;Hopkins et al, 2004;Lagnado et al, 2006;Meeter et al, 2006;Newell et al, 2007;Poldrack et al, 2001;Price, 2009), with hippocampus-dependent processes being particularly prevalent in the early stages of learning.…”

“…Behavioral and neuroimaging studies, however, have provided evidence that the WPT implicates both hippocampus‐dependent declarative processes and striatum‐dependent non‐declarative processes (Foerde et al., 2006, 2007; Gluck et al., 2002; Hopkins et al., 2004; Lagnado et al., 2006; Meeter et al., 2006; Newell et al., 2007; Poldrack et al., 2001; Price, 2009), with hippocampus‐dependent processes being particularly prevalent in the early stages of learning. Nevertheless, unduly influenced by the early reports purporting that the WPT specifically assessed striatal‐dependent procedural learning, many researchers have persisted in using the WPT and WPT‐like tasks for the explicit purposes of characterizing procedural learning and memory in typical and atypical development (e.g., Gabay & Goldfarb, 2017; Kemeny & Lukacs, 2010; Mayor‐Dubois et al., 2010, 2016), and the behavioral consequences of known or presumed structural or functional basal ganglia deficiencies in children and adults with, for example, attention‐deficit hyperactivity disorder (Gabay & Goldfarb, 2017), bulimia nervosa (Labouliere et al., 2016), schizophrenia (Fernandez et al., 2021; Foerde et al., 2008; Gomar et al., 2011; Horan et al., 2008; Karcher et al., 2019; Keri et al., 2000; Weickert et al., 2002), Parkinson and Huntington diseases (Knowlton, Mangels, et al., 1996; Knowlton, Squire, et al., 1996; Shohamy, Myers, Grossman, et al., 2004; Shohamy, Myers, Onlaor, et al., 2004), and Tourette syndrome (Keri et al., 2002; Marsh et al., 2004).…”