File Name: role of secondary sensory cortices in emotional memory storage and retrieval in rats .zip
- Role of secondary sensory cortices in emotional memory storage and retrieval in rats
- Primary auditory cortex regulates threat memory specificity
- A critical role of hippocampus for formation of remote cued fear memory
- Role of Secondary Sensory Cortices in Emotional Memory Storage and Retrieval in Rats
Role of secondary sensory cortices in emotional memory storage and retrieval in rats
A growing body of neurobiological and anatomic data continues to provide an increasingly detailed understanding of the role of amygdala in cognitive and motor control. We review evidence from past studies showing that the amygdala, which for many years was considered a black box,plays important roles in many neurobiological processes. The amygdala has key connections with the cortical areas, responsible for information processing that subserve emotion fear, anxiety ,learning, motor control, cognition, decision-making and social interaction. We conducted a review of current literature with studies that met inclusion criteria to synthesize findings on amygdala and their influence on the neurobiological aspects. The findings demonstate converging evidence that the amygdala plays a pivotal role in motor, cognitive and emotional functions.
Primary auditory cortex regulates threat memory specificity
The auditory cortex is involved in encoding sounds which have acquired an emotional—motivational charge. However, the neural circuitry engaged by emotional memory processes in the auditory cortex is poorly understood. In this study, we investigated the layers and regions that are recruited in the higher order auditory cortex Te2 by a tone previously paired to either fear or appetitive stimuli in rats. By tracking the protein coded by the immediate early gene zif , we found that fear memory retrieval engages layers II—III in most regions of Te2. These results were neither due to an enhanced fear state nor to fear-evoked motor responses, as they were absent in animals retrieving an olfactory fear memory. These layers were also activated by appetitive auditory memory retrieval.
Recent findings have shown that the auditory cortex, and specifically the higher order Te2 area, is necessary for the consolidation of long-term fearful memories and that it interacts with the amygdala during the retrieval of long-term fearful memories. Here, we tested whether the reversible blockade of Te2 during memory consolidation may affect the activity changes occurring in the amygdala during the retrieval of fearful memories. To address this issue, we blocked Te2 in a reversible manner during memory consolidation processes. After 4 weeks, we assessed the activity of Te2 and individual nuclei of the amygdala during the retrieval of long-term memories. Rats in which Te2 was inactivated upon memory encoding showed a decreased freezing and failed to show Te2-to-basolateral amygdala BLA synchrony during memory retrieval.
A critical role of hippocampus for formation of remote cued fear memory
Signal transmission from the human retina to visual cortex and connectivity of visual brain areas are relatively well understood. How specific visual perceptions transform into corresponding long-term memories remains unknown. Here, I will review recent Blood Oxygenation Level-Dependent functional Magnetic Resonance Imaging BOLD fMRI in humans together with molecular biology studies animal models aiming to understand how the retinal image gets transformed into so-called visual retinotropic maps. The broken object paradigm has been chosen in order to illustrate the complexity of multisensory perception of simple objects subject to visual —rather than semantic— type of memory encoding. The author explores how amygdala projections to the visual cortex affect the memory formation and proposes the choice of experimental techniques needed to explain our massive visual memory capacity.
Memory is the faculty of the brain by which data or information is encoded, stored, and retrieved when needed. It is the retention of information over time for the purpose of influencing future action. Memory is often understood as an informational processing system with explicit and implicit functioning that is made up of a sensory processor , short-term or working memory, and long-term memory.
Role of Secondary Sensory Cortices in Emotional Memory Storage and Retrieval in Rats
Distinguishing threatening from nonthreatening stimuli is essential for survival and stimulus generalization is a hallmark of anxiety disorders. While auditory threat learning produces long-lasting plasticity in primary auditory cortex Au1 , it is not clear whether such Au1 plasticity regulates memory specificity or generalization. We used muscimol infusions in rats to show that discriminatory threat learning requires Au1 activity specifically during memory acquisition and retrieval, but not during consolidation. Our findings show that Au1 is required at critical memory phases and suggest that Au1 plasticity enables stimulus discrimination. Two parallel neural pathways convey auditory information to the lateral nucleus of the amygdala where associative plasticity occurs during Pavlovian threat conditioning. Either of these pathways, the thalamo-amygdala and the thalalamo-cortico-amygdala pathway, can independently support auditory threat fear learning Romanski and LeDoux b ; Campeau and Davis ; Antunes and Moita , but the conditions that engage the cortical route and its functional role in threat memory are poorly understood Grosso et al.
Skip to search form Skip to main content You are currently offline. Some features of the site may not work correctly. DOI: Sacco and B. Sacco , B. Sacchetti Published Psychology, Medicine Science.
Metrics details. A unique feature of fear memory is its persistence that is highly relevant to fear and anxiety-related mental disorders. Recurrent reactivation of neural representations acquired from a traumatic event is thought to contribute to the indelibility of fear memory. Given a well-established role of hippocampus for memory reactivation, hippocampus is likely involved in consolidation process of fear memory. However, evidence suggests that formation of fear memory to a discrete sensory cue is hippocampus-independent.
Visual, acoustic, and olfactory stimuli associated with a highly charged emotional situation take on the affective qualities of that situation. Where the emotional meaning of a given sensory experience is stored is a matter of debate. We found that excitotoxic lesions of auditory, visual, or olfactory secondary sensory cortices impaired remote, but not recent, fear memories in rats. Amnesia was modality-specific and not due to an interference with sensory or emotional processes. In these sites, memory persistence was dependent on ongoing protein kinase Mzeta activity and was associated with an increased activity of layers II-IV, thus suggesting a synaptic strengthening of corticocortical connections. Lesions of the same areas left intact the memory of sensory stimuli not associated with any emotional charge.
Но система безопасности АНБ была лучшей в мире. Никому даже близко не удалось подойти к базе АНБ, и у агентства не было оснований полагать, что это когда-нибудь случится в будущем. Вернувшись в лабораторию, Чатрукьян никак не мог решить, должен ли он идти домой.
Судьба в это утро не была благосклонна к Беккеру. Выбегая из собора в маленький дворик, он зацепился пиджаком за дверь, и плотная ткань резко заставила его остановиться, не сразу разорвавшись. Он потерял равновесие, шатаясь, выскочил на слепящее солнце и прямо перед собой увидел лестницу. Перепрыгнув через веревку, он побежал по ступенькам, слишком поздно сообразив, куда ведет эта лестница.
Возле фреоновых помп. Сьюзан повернулась и направилась к двери, но на полпути оглянулась. - Коммандер, - сказала .
Сьюзан, извини. Это кошмар наяву.