Joshua Sandry1, Mark Zuppichini2, Jessica Rothberg1, Zerbrina Valdespino-Hayden1, John DeLuca3. 1. Psychology Department, Montclair State University, 1 Normal Ave Montclair, NJ, USA. 2. School of Behavioral & Brain Sciences, The University of Texas at Dallas, Richardson, TX, USA. 3. Kessler Foundation, West Orange, NJ, USA.
Abstract
OBJECTIVE: Learning and memory impairments are common in multiple sclerosis (MS) and may be related to difficulty acquiring (encoding or consolidating) new information. We evaluate the role of retroactive interference and investigate whether minimizing interference immediately following encoding (early during consolidation) will improve MS participants' ability to remember new verbal information. Additionally, we investigate processing speed differences between memory-impaired and unimpaired participants and present an exploratory analysis of how the dual-components of working memory (capacity vs. processing) relate to memory impairment. METHOD: MS memory-unimpaired (N = 12) and MS memory-impaired participants (N = 12) were compared to healthy controls (N = 15). Interference onset following encoding (early, mid, late, no interference) was manipulated over the retention interval of a verbal learning and memory task. Response times (RT) were recorded during interference trials. RESULTS: MS memory-impaired participants encoded less information and lost proportionally more information over the retention interval (weak consolidation). Lengthening the onset of interference did not benefit memory performance in this sample. Memory performance was unrelated to RT but was related to performance on the Symbol Digit Modalities Test. Primary capacity of working memory did not differ across groups; however, secondary memory processing was reduced for MS memory-impaired participants. CONCLUSION: Minimizing interference following encoding did not improve memory in this sample. Both initial encoding and early consolidation were reduced for memory-impaired MS participants. Evidence for a relationship between processing speed and memory was mixed and depended on the processing speed assessment used. Memory impairment in MS may be partially due to inefficient processing within working memory.
OBJECTIVE: Learning and memory impairments are common in multiple sclerosis (MS) and may be related to difficulty acquiring (encoding or consolidating) new information. We evaluate the role of retroactive interference and investigate whether minimizing interference immediately following encoding (early during consolidation) will improve MS participants' ability to remember new verbal information. Additionally, we investigate processing speed differences between memory-impaired and unimpaired participants and present an exploratory analysis of how the dual-components of working memory (capacity vs. processing) relate to memory impairment. METHOD: MS memory-unimpaired (N = 12) and MS memory-impaired participants (N = 12) were compared to healthy controls (N = 15). Interference onset following encoding (early, mid, late, no interference) was manipulated over the retention interval of a verbal learning and memory task. Response times (RT) were recorded during interference trials. RESULTS: MS memory-impaired participants encoded less information and lost proportionally more information over the retention interval (weak consolidation). Lengthening the onset of interference did not benefit memory performance in this sample. Memory performance was unrelated to RT but was related to performance on the Symbol Digit Modalities Test. Primary capacity of working memory did not differ across groups; however, secondary memory processing was reduced for MS memory-impaired participants. CONCLUSION: Minimizing interference following encoding did not improve memory in this sample. Both initial encoding and early consolidation were reduced for memory-impaired MS participants. Evidence for a relationship between processing speed and memory was mixed and depended on the processing speed assessment used. Memory impairment in MS may be partially due to inefficient processing within working memory.
Authors: Jordi A Matias-Guiu; Ana Cortés-Martínez; Rosie E Curiel; Alfonso Delgado-Álvarez; Aníbal Fernández-Oliveira; Vanesa Pytel; Paloma Montero; Teresa Moreno-Ramos; David A Loewenstein; Jorge Matías-Guiu Journal: Front Neurol Date: 2020-04-21 Impact factor: 4.086