May 4, 2024

Traumatic vs. Sad memories: How PTSD Alters Brain Function

” For people with PTSD, recalling distressing memories typically displays as invasions that vary profoundly from processing of regular unfavorable memories, yet up until now, the neurobiological reasons for this qualitative distinction have actually been improperly comprehended,” stated Daniela Schiller, PhD, Professor of Psychiatry, and Neuroscience, at Icahn Mount Sinai and senior author of the paper. “Our information reveal that the brain does not deal with traumatic memories as routine memories, or maybe even as memories at all. The team assumed that throughout PTSD individuals, semantic resemblance would correspond to neural resemblance: if the individual memories of 2 individuals are semantically close, their patterns of neural responses while listening to audio recordings of these memories need to be comparable. If sad and distressing memories are just various cases of autobiographical memories, the researchers anticipated to observe semantic-to-neural correspondence throughout pairs of distressing memories and pairs of sad memories alike. If distressing autobiographical memories leave from– rather than being a version of– sad autobiographical memories, then they would observe the semantic-to-neural relationship just for sad, however not traumatic, memories.

Scientists at the Icahn School of Medicine and Yale University found that in PTSD, traumatic memories are processed in a different way in the brain compared to unfortunate memories, with unique neural patterns in the hippocampus and PCC. This finding, released in Nature Neuroscience, suggests brand-new treatment methods for PTSD focusing on altering the brains processing of terrible memories.
A study reveals that PTSD affects how the brain processes traumatic memories in a different way from sad memories, providing insights for targeted treatments.
A brand-new analysis of the brain activity of individuals with trauma (PTSD) is the very first to expose that distressing memories are represented in the brain in a completely various method than unfortunate autobiographical memories.
This finding supports the concept that distressing memories in PTSD are an alternate cognitive entity that deviates from regular memory, and might offer a biological description for why the recall of terrible memories often shows as intrusions that differ profoundly from “regular” negative memories for patients with PTSD.

Connecting Personal Experience to Brain Function
The study, conducted by researchers at the Icahn School of Medicine at Mount Sinai and Yale University and published today (November 30) in the journal Nature Neuroscience, was also the very first to take a look at individualss real-life personal memories rather than taking a look at fundamental cognitive systems, in order to link personal experience to brain function.
” For individuals with PTSD, remembering distressing memories frequently shows as intrusions that vary exceptionally from processing of routine negative memories, yet up until now, the neurobiological factors for this qualitative distinction have actually been improperly understood,” said Daniela Schiller, PhD, Professor of Psychiatry, and Neuroscience, at Icahn Mount Sinai and senior author of the paper. “Our data show that the brain does not treat terrible memories as regular memories, or possibly even as memories at all.
Memory Processing in PTSD
Previous research has actually developed that the brain region understood as the hippocampus governs the development and retrieval of episode memories. PTSD is associated with structural irregularities (mainly a decrease of volume) of the hippocampus, and disabilities to hippocampal processes are focal to PTSD pathophysiology. The posterior cingulate cortex (PCC) has actually been shown to be greatly included in both narrative understanding and autobiographical processing and, especially, in psychological memory imagery. Changes in PCC function and connectivity are particularly focal to PTSD.
Research Study Methodology and Findings
To examine whether and how the hippocampus and posterior cingulate cortex distinguish terrible autobiographical memories from sad ones, 28 participants detected with PTSD underwent reactivation of autobiographical memory through script-driven images while undergoing functional magnetic resonance imaging (fMRI).
To generate stimuli based on individuals specific autobiographical memories, the researchers utilized an images development procedure. Participants elaborated on three kinds of autobiographical memories: the “PTSD” condition: the terrible memory connected with their PTSD (e.g., battle, sexual attack, domestic violence), the “unfortunate” condition: a sad, significant, however non-traumatizing experience (e.g., death of a relative or family pet), the “calm” condition: a favorable, calm event (e.g., memorable outside activities).
These highly individual representations of autobiographical memory were then methodically arranged into an audio clip approximately 120 seconds long, told by a member of the research personnel. Especially, the PTSD and sad narratives were scripted to optimize their structural similarity to each other, to control for content and arousal. Participants listened to this unique rendition of their own memories for the very first time while undergoing functional magnetic resonance imaging.
The team assumed that across PTSD individuals, semantic resemblance would correspond to neural resemblance: if the individual memories of two individuals are semantically close, their patterns of neural reactions while listening to audio recordings of these memories ought to be similar also. If distressing and unfortunate memories are just various cases of autobiographical memories, the scientists anticipated to observe semantic-to-neural correspondence throughout sets of terrible memories and sets of unfortunate memories alike. Nevertheless, if terrible autobiographical memories depart from– instead of being a version of– sad autobiographical memories, then they would observe the semantic-to-neural relationship only for unfortunate, but not traumatic, memories.
Distinguishing Traumatic and Sad Memories
The research group was captivated to find that patterns in the hippocampus revealed a differentiation in semantic representation by narrative type. In the hippocampus, sad scripts that were semantically similar throughout individuals generated similar neural representations on fMRI. On the other hand, thematically comparable distressing autobiographical memories did not generate comparable representations.
Importantly, the scientists likewise discovered a favorable relationship between semantic material and neural patterns of the traumatic narratives in the PCC, a brain region that was recently conceived as a cognitive bridge between the world occasions and representation of the self.
Implications for PTSD Treatment
The research study determines a neural basis of the various subjective experience of recalling a traumatic memory rather than a routine memory. The information recommends that a treatment target focused on “returning” the distressing memory representation into a common hippocampal representation might be beneficial.
Reference: “Neural patterns distinguish terrible from unfortunate autobiographical memories in PTSD” 30 November 2023, Nature Neuroscience.DOI: 10.1038/ s41593-023-01483-5.
NIH/National Institutes of Health, Brain and Behavior Research Foundation, National Center for PTSD.