Semantic memory

What circuit mechanisms underlie the encoding and retrieval of spatial memory? In standard models, neurons have discrete fields that map onto locations, which are associated with actions [1]. Given that spatial-memory regions (such as hippocampus and entorhinal cortex) have recurrent architectures, it is unclear if this feedforward association mechanism is the only way in which spatial memories can be stored. Here, we propose a new mechanism for spatial memory that is derived from reverse-engineering recurrent neural networks (RNNs). We train RNNs on a spatial navigation task posed as a rein

…types of symbols are processed semantically, or it might be a byproduct of activities related to imagining scenes associated with the meanings of these symbols. To address this debate, we simulated the semantic learning of realistic action words i

The serotonergic system was previously shown to affect learning and memory processes in humans[1]. Establishing a relation between serotonin-1A receptor (5-HT1AR) distribution with memory processing would allow us to further investigate its potential as a therapeutic target. Here, we aim to investigate the effect of 5-HT1AR spatial distribution on the different memory domains. Positron emission tomography data were collected from 20 healthy volunteers using the radioligand [carbonyl-11C]WAY-100635 [2,3]. Data were quantified using multilinear reference tissue model 2 to obtain non-displaceable

Semantic memory and abstraction of knowledge from experience are thought to involve communication between the hippocampus and neocortex. The hippocampus encodes novel episodes using sparse and orthogonal neural representations, which form and stabilize within ~10 minutes in a novel environment. Recent studies have shown that several neocortical areas, including the retrosplenial cortex (RSC), primary somatosensory cortex (S1), and primary visual cortex (V1) contain sparse neural coding correlated to spatial location in one-dimensional environments. This spatial coding depends on an intact hipp

…range of cognitive functions including semantic memory, recognition memory, attention and visual function. We have shown that Fastball is sensitive to cognitive dysfunction in Alzheimer’s disease and Mild Cognitive Impairment, with data collected in patients’ homes using low-cost portable EEG. We are n