Working memory and processing speed training in schizophrenia: study protocol for a randomized controlled trial

Abstract

BackgroundIn most domains of cognition, individuals with schizophrenia are generally found to be one standard deviation below the mean of the controls. As a result, examining the impact of cognitive remediation in individuals with schizophrenia has been a burgeoning area of research. However, the state of the literature remains unclear as to which domains of cognition should be targeted to produce the most widespread and durable benefits for individuals with schizophrenia. One suggestion is that targeting lower-level cognitive processes that are important for higher-level and more complex aspects of cognition may produce the most widespread benefits in cognition and everyday functioning. Relatively few studies have examined the effects of working memory or processing speed training in schizophrenia, as most studies examine broad-based remediation programs. Thus, a need exists for targeted working memory and processing speed training studies to better understand the mechanisms of cognitive enhancement in patients. This study aims to 1) investigate near-transfer gains (that is, the transfer of learning to related contexts) associated with working memory and processing speed training in schizophrenia patients; 2) investigate far-transfer gains (that is, the transfer of learning to new contexts) associated with working memory and processing speed training (that is, gains in other neurocognitive domains and social cognition); and 3) investigate real-world gains associated with training (that is, gains in daily functioning).Methods/DesignA double-blind randomized controlled trial with a three parallel group design will be conducted. A random sample of 81 patients with schizophrenia or schizoaffective disorder will be recruited through outpatient clinics at Foothills Hospital and community support programs in Calgary, Alberta. Participants will be randomly assigned using a computer-generated program in a 1:1:1 ratio to a working memory-training group, a processing speed-training group, or a no-training control group. Training will be completed at home for 30 minutes per day, 5 days per week, for a total of 10 weeks. Neurocognitive, social cognitive, and daily functioning measures will be administered both pre- and post-training to detect training-related gains. The primary outcome measures will include working memory and processing speed (near-transfer measures), as well as fluid intelligence (far-transfer measure).Trial registrationCurrent controlled trials NCT02478827 (ClinicalTrials.gov, registered on 15 June 2015).Electronic supplementary materialThe online version of this article (doi:10.1186/s13063-016-1188-5) contains supplementary material, which is available to authorized users.

Generalized neurocognitive impairment in individuals at ultra‐high risk for psychosis: The possible key role of slowed processing speed

“…Processing speed appears to be particularly important to measure in UHR individuals, also for screening purposes (González‐Blanch et al., 2011), because it may capture the generalized impairment. From a treatment perspective, our study may provide a rationale for targeting this apparently domain‐general neurocognitive mechanism, using behavioral and/or pharmacological interventions to boost neurocognitive processing efficiency (Brébion et al., 2014; Cassetta & Goghari, 2016; Cassetta et al., 2019; Takeuchi & Kawashima, 2012). Thus, a double‐blind randomized clinical trial has shown that UHR individuals receiving processing speed training exhibit improvement not only in processing speed but also in social functioning (Choi et al., 2017).…”

A randomized controlled trial of working memory and processing speed training in schizophrenia

“…The full rationale and methodology of the present study was previously published (Cassetta and Goghari, 2016) and registered online at ClinicalTrials.gov (registration number: NCT02478827). The current study was a randomized controlled trial (RCT) that employed a parallel design with a 1:1:1 allocation ratio.…”

“…As previously described (Cassetta and Goghari, 2016), all participants were administered the following measures at pre- and post-assessment: three measures of WM (N-Back, maintenance and manipulation task, and digit span), two measures of PS (symbol search and color naming from the Delis–Kaplan Executive Function System [DKEFS]), two measures of fluid intelligence (Raven's Standard Progressive Matrices [RSPM] and Cattell's Culture Fair Test [CCFT]), three measures of executive functioning (EF; DKEFS Color-Word Interference Test [CWIT]-Inhibition Scale, DKEFS CWIT-Switching Scale, DKEFS Trail Making Test [TMT]-Switching Subtest), two measures of social cognition (The Hinting Task and the Geneva Emotion Recognition Test [GERT]), four measures of daily functioning/symptomatology (the Cognitive Failures Questionnaire [CFQ], UCSD Performance-Based Skills Assessment Brief [UPSA Brief], Social and Occupational Functioning Assessment Scale [SOFAS], and the Positive and Negative Syndrome Scale [PANSS]), and two measures of beliefs regarding cognition (Need for Cognition Scale and Theories of Intelligence Scale). The primary outcome measures (i.e.…”

Efeito do treinamento de artes marciais no desempenho das funções executivas e nos sintomas do transtorno do déficit de atençãoo/hiperatividade em crianças de nove a 12 anos

“…As Funções Executivas (FEs) são mecanismos A memória operacional é responsável pelo armazenamento, organização e manipulação de múltiplas informações em um curto espaço de tempo (Cassetta et al, 2016;Müller et al, 2002), portanto, essencial para o planejamento, aprendizagem e compreensão de qualquer interação de linguagem, seja ela oral ou gráfica (Diamond, 2012).…”

“…Grupos com TDAH exibiram comprometimento significativo em todas as tarefas de FEs. Os efeitos mais fortes e consistentes foram obtidos nas medidas de capacidade inibitória e memória de operacional.Os estudos deCastellanos et al,2006;Matthews et al, 2014) enfatizaram a importância das questões de heterogeneidade para a a definição de conceitos e abordagens atuais no TDAH ao apontar que, embora exista um padrão de compromentimento das funções executivas nos portadores, a apresentação dessa deficiência varia drasticamente.As funções executivas são apontadas como fator principal nas dificuldades sociais, emocionais e acadêmica das crianças com TDAH (Barkley,2005) e determinantes na diminuição de seus sintomas quando estimuladas em treinamentos e intervenções que envolvam atividade motora. As práticas de intervenção serão mais eficazes se propuserem estimulação simultânea das múltiplas funções que costumam estar deficientes em crianças com TDAH…”