Two experiments (modeled after J. Deese's 1959 study) revealed remarkable levels of false recall and false recognition in a list learning paradigm. In Experiment 1, subjects studied lists of 12 words (e.g., bed, rest, awake); each list was composed of associates of 1 nonpresented word (e.g., sleep). On immediate free recall tests, the nonpresented associates were recalled 40% of the time and were later recognized with high confidence. In Experiment 2, a false recall rate of 55% was obtained with an expanded set of lists, and on a later recognition test, subjects produced false alarms to these items at a rate comparable to the hit rate. The act of recall enhanced later remembering of both studied and nonstudied material. The results reveal a powerful illusion of memory: People remember events that never happened.
Summary
Human functional MRI (fMRI) research primarily focuses on analyzing data averaged across groups, which limits the detail, specificity, and clinical utility of fMRI resting-state functional connectivity (RSFC) and task activation maps. To push our understanding of functional brain organization to the level of individual humans, we assembled a novel MRI dataset containing five hours of RSFC data, six hours of task fMRI, multiple structural MRIs, and neuropsychological tests from each of ten adults. Using these data, we generated ten high fidelity, individual-specific functional connectomes. This individual connectome approach revealed several new types of spatial and organizational variability in brain networks, including unique network features and topologies that corresponded with structural and task-derived brain features. We are releasing this highly-sampled, individual-focused dataset as a resource for neuroscientists, and we propose precision individual connectomics as a model for future work examining the organization of healthy and diseased individual human brains.
Summary
Resting state functional MRI has enabled description of group-level
functional brain organization at multiple spatial scales. However, cross-subject
averaging may obscure patterns of brain organization specific to each
individual. Here, we characterized the brain organization of a single individual
repeatedly measured over more than a year. We report a reproducible and
internally valid subject-specific areal-level parcellation that corresponds with
subject-specific task activations. Highly convergent correlation network
estimates can be derived from this parcellation if sufficient data are collected
– considerably more than typically acquired. Notably, within-subject
correlation variability across sessions exhibited a heterogeneous distribution
across the cortex concentrated in visual and somato-motor regions, distinct from
the pattern of inter-subject variability. Further, although the individual's
systems-level organization is broadly similar to the group, it demonstrates
distinct topological features. These results provide a foundation for studies of
individual differences in cortical organization and function, especially for
special or rare individuals.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.