Proc Natl Acad Sci U S A
October 2023
Failure of contextual retrieval can lead to false recall, wherein people retrieve an item or experience that occurred in a different context or did not occur at all. Whereas the hippocampus is thought to play a crucial role in memory retrieval, we lack understanding of how the hippocampus supports retrieval of items related to a target context while disregarding related but irrelevant information. Using direct electrical recordings from the human hippocampus, we investigate the neural process underlying contextual misattribution of false memories.
View Article and Find Full Text PDFObjective: The current study investigated the oscillatory brain activity of PTSD patients during directed and imaginal exposure to the traumatic memory using magnetoencephalography (MEG), in a paradigm resembling exposure therapy.
Methods: Brain activity of healthy trauma-exposed controls and PTSD participants was measured with MEG as they listened to individualized trauma narratives as well as to a neutral narrative and as they imagined the narrative in detail. Source localization analysis by frequency bands was conducted in order to map neural generators of oscillatory activity.
Aversive events can be reexperienced as involuntary and spontaneous mental images of the event. Given that the vividness of retrieved mental images is coupled with elevated visual activation, we tested whether neuromodulation of the visual cortex would reduce the frequency and negative emotional intensity of intrusive memories. Intrusive memories of a viewed trauma film and their accompanied emotional intensity were recorded throughout 5 days.
View Article and Find Full Text PDFConditions in which memories become maladaptive have inspired extensive research geared to modulate memory by targeting it directly and explicitly. Given limitations of direct memory modulation, we asked the following: can the target memories be modulated indirectly? To address this question, we uniquely targeted visual memories, and leveraged a paradigm utilizing instructions to either forget or remember newly encoded memories. We used a multi-domain approach, and applied the instructions to embedded verbal information presented during encoding (words), with the intention to indirectly modulate recognition of the target visual context memory itself (pictures).
View Article and Find Full Text PDFBehav Res Ther
December 2020
Memories of negative emotional events persist more over time relative to memories for neutral information. Such persistence has been attributed to heightened encoding and consolidation processes. However, reactivation of the encoded information may also lead to reduced memory decay through rehearsal or a reconsolidation processes.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
July 2020
We all have our varying mental emphases, inclinations, and biases. These individual dispositions are dynamic in that they can change over time and context. We propose that these changing states of mind (SoMs) are holistic in that they exert all-encompassing and coordinated effects simultaneously on our perception, attention, thought, affect, and behavior.
View Article and Find Full Text PDFObjectives: We investigated whether the central pain symptoms in fibromyalgia syndrome (FM) are related to defective top-down sensorimotor regulation. The pain matrix was activated in a top-down manner by presenting pictures of painful situations while recording brain activity using magnetoencephalography (MEG). We investigated alpha desynchronisation in FM patients and healthy controls in response to pictures depicting pain.
View Article and Find Full Text PDFClin Neurophysiol
October 2016
Objective: Patients suffering from posttraumatic stress disorder (PTSD) exhibit hyper arousal symptoms and attention problems which were frequently investigated using the P3 event-related potentials (ERPs). Our study aimed at providing more precise knowledge of the functional significance of the P3 alteration seen in PTSD by revealing its spatio-temporal dynamics.
Methods: Fifteen PTSD patients and fifteen healthy trauma-exposed controls participated in a three-tone "oddball" task while their brain activity was recorded by magnetoencephalography (MEG).