Publications by authors named "Anne T A Do Lam"
Background: The psychodynamic theory of repression suggests that experiences which are related to internal conflicts become unconscious. Previous attempts to investigate repression experimentally were based on voluntary, intentional suppression of stimulus material. Unconscious repression of conflict-related material is arguably due to different processes, but has never been studied with neuroimaging methods.
View Article and Find Full Text PDFWhich neural processes underlie our conscious experience? One theoretical view argues that the neural correlates of consciousness (NCC) reside in local activity in sensory cortices. Accordingly, local category-specific gamma band responses in visual cortex correlate with conscious perception. However, as most studies manipulated conscious perception by altering the amount of sensory evidence, it is possible that they reflect prerequisites or consequences of consciousness rather than the actual NCC.
View Article and Find Full Text PDFZero-lag phase synchronization of EEG activity has been reported to be a central mechanism accompanying long-term memory formation. In this pilot study, we examined the effects of synchronous low-amplitude stimulation of the rhinal cortex and the hippocampus in eleven temporal lobe epilepsy patients. The impact of in-phase stimulation (zero lag) on long-term memory encoding of words was contrasted with anti-phase (180° phase lag) and sham stimulation.
View Article and Find Full Text PDFIn the endeavor to understand how our brains enable our multifaceted memories, much controversy surrounds the contributions of the hippocampus and perirhinal cortex (PrC). We recorded functional magnetic resonance imaging (fMRI) in healthy controls and intracranial electroencephalography (EEG) in patients during a recognition memory task. Although conventional fMRI analysis showed indistinguishable roles of the hippocampus and PrC in familiarity-based item recognition and recollection-based source retrieval, event-related fMRI and EEG time courses revealed a clear temporal dissociation of memory signals in and across these regions.
View Article and Find Full Text PDFArticle Synopsis
- Memory performance often requires monitoring through metamemory evaluations like judgments of learning (JOLs), which help adjust learning strategies.
- Behavioral studies suggest that retrieval processes are fundamental to how JOLs are formed.
- Using fMRI, this research identified that actual memory success activates the hippocampi, while predicted memory success is linked to increased activity in the medial prefrontal cortex and related areas, showing that JOLs involve retrieval processes.
Article Synopsis
- The text discusses challenges in studying memory processes related to repression and trauma using conventional cognitive neuroscience methods, emphasizing the complexity of these experiences.
- It highlights how memory impairments, like those seen in PTSD and internal conflicts, lead to unconscious psychological issues, but existing research methods may not properly reflect these processes.
- The authors propose a need for new experimental frameworks that examine memory through a constructivist lens, focusing on how experiences are integrated into the self, to understand the neural basis of repressed memories and distortions.