Article
Neurosciences
Ghislain Belliart-Guerin, Vincent Planche
Summary: This study assessed the clinical relevance of mnemonic discrimination and found that it could discriminate between patients with subjective cognitive complaint (SCC) and mild cognitive impairment (MCI). Mnemonic discrimination involves multiple cognitive domains and performs similarly to other commonly used tests.
JOURNAL OF ALZHEIMERS DISEASE
(2023)
Article
Neurosciences
Javier Ortiz-Tudela, Johanna Bergmann, Matthew Bennett, Isabelle Ehrlich, Lars Muckli, Yee Lee Shing
Summary: Efficient processing of the visual environment requires integrating sensory evidence, contextual inputs, and mnemonic content. In this study, we investigated how this integration occurs in the brain by isolating different types of feedback signals from non-stimulated areas of the early visual cortex. Our findings showed that both contextual and time-distant information coexist as feedback signals in V1 and V2. We also observed that the reinstatement of mnemonic information in V1 and V2 depends on episodic or semantic retrieval, independent of the retrieval route in the object-selective cortex.
Article
Psychology, Multidisciplinary
George Samrani, Anders Lundquist, Sara Pudas
Summary: Declarative memory abilities change across adulthood. Semantic memory and autobiographic episodic knowledge can remain stable or even increase from mid- to late adulthood, while episodic memory abilities decline in later adulthood. An increased reliance on memory integration may be an adaptive mechanism to handle increased interference from accumulating memory traces and knowledge across adulthood. Middle-aged adults show age-equivalent performance on integration and discrimination measures, along with higher verbal knowledge and slower perceptual speed compared to younger adults.
FRONTIERS IN PSYCHOLOGY
(2022)
Article
Biology
Helen Blank, Janine Bayer
Summary: Model-based analyses of fMRI data provide insights into the neural basis of similarity-based categorization. Prototype and exemplar representations were found in different brain areas, and some individuals formed both representation types simultaneously.
COMMUNICATIONS BIOLOGY
(2022)
Article
Neurosciences
Youssef Ezzyat, James E. Kragel, Ethan A. Solomon, Bradley C. Lega, Joshua P. Aronson, Barbara C. Jobst, Robert E. Gross, Michael R. Sperling, Gregory A. Worrell, Sameer A. Sheth, Paul A. Wanda, Daniel S. Rizzuto, Michael J. Kahana
Summary: Closed-loop direct brain stimulation can improve episodic memory, especially when targeted at regions near white matter pathways with high functional connectivity to the brain's memory network. The anatomical and functional network properties of the stimulation target play a crucial role in its behavioral and physiological effects.
Article
Multidisciplinary Sciences
Jacob L. S. Bellmund, Lorena Deuker, Nicole D. Montijn, Christian F. Doeller
Summary: The hippocampal-entorhinal region plays a crucial role in supporting memory for episodic details, including temporal relations, mnemonic constructions, and structural knowledge generalization.
NATURE COMMUNICATIONS
(2022)
Article
Neurosciences
Alexander W. Baumann, Theo A. J. Schaefer, Hannes Ruge
Summary: Learning new rules rapidly and effectively is common in daily life, but the cognitive and neural mechanisms behind it are complex. Using functional magnetic resonance imaging, researchers studied the effects of different instructional load conditions on the brain's couplings during rule implementation. The results showed differences in how the brain processes instructions and how it handles conflicting information when the load exceeds working memory capacity. Additionally, the ventrolateral prefrontal cortex exhibited hemispherical differences in whole-brain coupling and practice-related dynamics.
Article
Neurosciences
Thomas M. Morin, Kylie N. Moore, Kylie Isenburg, Weida Ma, Chantal E. Stern
Summary: This study examined the symbolic and perceptual reasoning of human participants undergoing fMRI scanning using a modified Raven's Progressive Matrices Task. The findings showed that frontoparietal networks were significantly activated during abstract reasoning and exhibited flexibly-reconfigured functional connectivity when transitioning from resting state to the abstract reasoning task. In contrast, a stable network core in default and somatomotor networks was maintained across both resting and task states.
Article
Neurosciences
Kshipra Gurunandan, Manuel Carreiras, Pedro M. Paz-Alonso
Summary: This study reveals the functional plasticity in language production among adult language learners, demonstrating the impact of language learning on neural correlates, and providing new insights into the verbal fluency task.
Article
Multidisciplinary Sciences
Dona Kandaleft, Kou Murayama, Etienne Roesch, Michiko Sakaki
Summary: Emotion-laden events and objects are better remembered than neutral ones, which is usually explained by increased functional coupling in the brain. However, there may be little or no association between individual differences in functional connectivity at rest and emotional memory.
SCIENTIFIC REPORTS
(2022)
Article
Neuroimaging
Hao Shu, Lihua Gu, Ping Yang, Molly Lucas, Lijuan Gao, Hongxing Zhang, Haisan Zhang, Zhan Xu, Wei Wu, Ling Li, Zhijun Zhang
Summary: The study found disturbed temporal dynamics in episodic retrieval activity but preserved spatial activity pattern in patients with amnestic mild cognitive impairment (aMCI). Simultaneous EEG-fMRI technique demonstrated potential to identify individuals at high risk of cognitive deterioration.
NEUROIMAGE-CLINICAL
(2021)
Article
Neurosciences
Francesco Neri, Stefano F. Cappa, Lucia Mencarelli, Davide Momi, Emiliano Santarnecchi, Simone Rossi
Summary: This study investigated the recruitment of brain networks during story recollection process using an ecological fMRI free recall task. The results showed that free recall enhanced the activity of brain networks such as language, left executive control, default mode, and precuneus. The recruitment of the anterior angular gyrus may serve as a marker for optimal functioning in the recall process.
Article
Neurosciences
Liisa Raud, Markus H. Sneve, Didac Vidal-Pineiro, Oystein Sorensen, Line Folvik, Hedda T. Ness, Athanasia M. Mowinckel, Hakon Grydeland, Kristine B. Walhovd, Anders M. Fjell
Summary: Memory encoding and retrieval are important processes in episodic memory, with the hippocampus playing a key role. However, the connectivity between the hippocampus and neocortex during memory processing in humans is not well understood. This study used data from two large-scale functional resonance imaging studies to identify hippocampal-cortical networks active during memory tasks. The functional connectivity maps were similar during resting state, encoding, and retrieval, and the connectivity profiles of the anterior and posterior hippocampus were stable across different states. During retrieval, the hippocampal connectivity with areas involved in recollection increased, while encoding connectivity likely reflected contextual factors.
Article
Neurosciences
Michelle I. Nash, Cooper B. Hodges, Nathan M. Muncy, C. Brock Kirwan
Summary: This study utilized high-resolution functional MRI scanning to identify activation patterns consistent with pattern separation in distinct hippocampal subregions, particularly in the subiculum. Connectivity analyses revealed a network of cortical regions consistent with the memory retrieval network where fMRI activation was correlated with hippocampal activation, suggesting that a network of brain regions contribute to mnemonic discrimination performance.
Article
Neurosciences
Wenchao Zhang, Guanya Li, Peter Manza, Yang Hu, Jia Wang, Ganggang Lv, Yang He, Karen M. von Deneen, Juan Yu, Yu Han, Guangbin Cui, Nora D. Volkow, Yongzhan Nie, Gang Ji, Gene-Jack Wang, Yi Zhang
Summary: Compared to individuals with normal weight, individuals with obesity show a preference for immediate rewards of food intake and are less interested in the delayed reward of healthy well-being achieved through diet management and physical activity. The greater impulsivity in individuals with obesity may be due to aberrant function and connectivity in core brain regions involved in cognitive control and reward processing.
Article
Neurosciences
Jose Sanchez-Bornot, Roberto C. Sotero, J. A. Scott Kelso, Ozguer Simsek, Damien Coyle
Summary: This study proposes a multi-penalized state-space model for analyzing unobserved dynamics, using a data-driven regularization method. Novel algorithms are developed to solve the model, and a cross-validation method is introduced to evaluate regularization parameters. The effectiveness of this method is validated through simulations and real data analysis, enabling a more accurate exploration of cognitive brain functions.