Stevan Nikolin1, Yi Yin Tan2, Andreas Schwaab2, Adriano Moffa2, Colleen K Loo3, Donel Martin4. 1. School of Psychiatry, University of New South Wales, Sydney, Australia; Black Dog Institute, Sydney, Australia. Electronic address: stevan.nikolin@unsw.edu.au. 2. School of Psychiatry, University of New South Wales, Sydney, Australia. 3. School of Psychiatry, University of New South Wales, Sydney, Australia; Black Dog Institute, Sydney, Australia; St. George Hospital, Sydney, Australia. 4. School of Psychiatry, University of New South Wales, Sydney, Australia; Black Dog Institute, Sydney, Australia.
Abstract
BACKGROUND: Depression is associated with cognitive deficits across multiple domains, including working memory. The n-back task, a convenient psychometric tool capable of computerised delivery and concurrent use with neuroimaging, can provide enhanced insight into working memory dysfunction in depression. This meta-analysis sought to investigate the n-back task under varying cognitive load conditions (i.e. different levels of 'n') to clarify the pattern of working memory deficits in depression. METHODS: We conducted a systematic review and meta-analysis of studies involving unipolar depressed participants and matched controls utilising the n-back task. Meta-analyses were performed for accuracy and response times at four levels of cognitive load (0-, 1-, 2-, and 3-back). RESULTS: 31 studies (total 1,666 participants) met inclusion criteria and were included for quantitative analyses. Depressed individuals had significantly reduced accuracy compared to controls for 1-, 2-, and 3-back tasks, but not the attentional 0-back task. Likewise, response latencies were prolonged for all task levels (0-, 1-, 2-, and 3-back). Additional meta-regression analyses indicated that participant age and clinical status (i.e. inpatient/outpatient) may exacerbate working memory deficits associated with depression. LIMITATIONS: Our results indicate high levels of heterogeneity between studies, particularly for response times. CONCLUSIONS: Accuracy impairments were worse at higher levels of n, with the largest effect size obtained on the 2-back task, suggesting deficits to higher executive functions. Response times were consistently prolonged at all cognitive loads in agreement with a pattern of generalised psychomotor retardation.
BACKGROUND:Depression is associated with cognitive deficits across multiple domains, including working memory. The n-back task, a convenient psychometric tool capable of computerised delivery and concurrent use with neuroimaging, can provide enhanced insight into working memory dysfunction in depression. This meta-analysis sought to investigate the n-back task under varying cognitive load conditions (i.e. different levels of 'n') to clarify the pattern of working memory deficits in depression. METHODS: We conducted a systematic review and meta-analysis of studies involving unipolar depressedparticipants and matched controls utilising the n-back task. Meta-analyses were performed for accuracy and response times at four levels of cognitive load (0-, 1-, 2-, and 3-back). RESULTS: 31 studies (total 1,666 participants) met inclusion criteria and were included for quantitative analyses. Depressed individuals had significantly reduced accuracy compared to controls for 1-, 2-, and 3-back tasks, but not the attentional 0-back task. Likewise, response latencies were prolonged for all task levels (0-, 1-, 2-, and 3-back). Additional meta-regression analyses indicated that participant age and clinical status (i.e. inpatient/outpatient) may exacerbate working memory deficits associated with depression. LIMITATIONS: Our results indicate high levels of heterogeneity between studies, particularly for response times. CONCLUSIONS: Accuracy impairments were worse at higher levels of n, with the largest effect size obtained on the 2-back task, suggesting deficits to higher executive functions. Response times were consistently prolonged at all cognitive loads in agreement with a pattern of generalised psychomotor retardation.
Authors: Cristina Delgado-Alonso; Maria Valles-Salgado; Alfonso Delgado-Álvarez; Miguel Yus; Natividad Gómez-Ruiz; Manuela Jorquera; Carmen Polidura; María José Gil; Alberto Marcos; Jorge Matías-Guiu; Jordi A Matías-Guiu Journal: J Psychiatr Res Date: 2022-03-24 Impact factor: 5.250
Authors: Anna Manelis; Yaroslav O Halchenko; Lisa Bonar; Richelle S Stiffler; Skye Satz; Rachel Miceli; Cecile D Ladouceur; Genna Bebko; Satish Iyengar; Holly A Swartz; Mary L Phillips Journal: Transl Psychiatry Date: 2022-10-11 Impact factor: 7.989