title: Goal-Directed Modulation of Neural Memory Patterns: Implications for fMRI-Based Memory Detection.
abstract: Remembering a past event elicits distributed neural patterns that can be distinguished from patterns elicited when encountering novel information. These differing patterns can be decoded with relatively high diagnostic accuracy for individual memories using multivoxel pattern analysis (MVPA) of fMRI data. Brain-based memory detection--if valid and reliable--would have clear utility beyond the domain of cognitive neuroscience, in the realm of law, marketing, and beyond. However, a significant boundary condition on memory decoding validity may be the deployment of "countermeasures": strategies used to mask memory signals. Here we tested the vulnerability of fMRI-based memory detection to countermeasures, using a paradigm that bears resemblance to eyewitness identification. Participants were scanned while performing two tasks on previously studied and novel faces: (1) a standard recognition memory task; and (2) a task wherein they attempted to conceal their true memory state. Univariate analyses revealed that participants were able to strategically modulate neural responses, averaged across trials, in regions implicated in memory retrieval, including the hippocampus and angular gyrus. Moreover, regions associated with goal-directed shifts of attention and thought substitution supported memory concealment, and those associated with memory generation supported novelty concealment. Critically, whereas MVPA enabled reliable classification of memory states when participants reported memory truthfully, the ability to decode memory on individual trials was compromised, even reversing, during attempts to conceal memory. Together, these findings demonstrate that strategic goal states can be deployed to mask memory-related neural patterns and foil memory decoding technology, placing a significant boundary condition on their real-world utility.
authors.affiliation: Department of Psychology and melina.u@stanford.edu.
authors.forename: Melina R
authors.initials: MR
authors.lastname: Uncapher
authors.affiliation: Department of Psychology and.
authors.forename: J Tyler
authors.initials: JT
authors.lastname: Boyd-Meredith
authors.affiliation: Department of Psychology, University of California, Los Angeles, Los Angeles, California 90095.
authors.forename: Tiffany E
authors.initials: TE
authors.lastname: Chow
authors.affiliation: Department of Psychology, University of California, Los Angeles, Los Angeles, California 90095.
authors.forename: Jesse
authors.initials: J
authors.lastname: Rissman
authors.affiliation: Department of Psychology and Neurosciences Program, Stanford University, Stanford, California 94305, and.
authors.forename: Anthony D
authors.identifier: http://orcid.org/0000-0003-0624-4543
authors.initials: AD
authors.lastname: Wagner
mesh_terms: D000293:Adolescent; D000328:Adult; D001288:Attention; D001921:Brain / Q000098:blood supply* / Q000502:physiology*; D001931:Brain Mapping; D005108:Extinction, Psychological; D005145:Face; D006040:Goals; D006801:Humans; D007091:Image Processing, Computer-Assisted; D033182:Intention; D008279:Magnetic Resonance Imaging; D008297:Male; D008568:Memory / Q000502:physiology*; D010100:Oxygen / Q000097:blood; D010775:Photic Stimulation; D011930:Reaction Time / Q000502:physiology; D055815:Young Adult
chemical_list: D010100:Oxygen
keywords: countermeasures; episodic retrieval; functional MRI; neurolaw; pattern classification