The Role of Anterior Nuclei of the Thalamus: A Subcortical Gate in Memory Processing: An Intracerebral Recording Study

Abstract

ObjectiveTo study the involvement of the anterior nuclei of the thalamus (ANT) as compared to the involvement of the hippocampus in the processes of encoding and recognition during visual and verbal memory tasks.MethodsWe studied intracerebral recordings in patients with pharmacoresistent epilepsy who underwent deep brain stimulation (DBS) of the ANT with depth electrodes implanted bilaterally in the ANT and compared the results with epilepsy surgery candidates with depth electrodes implanted bilaterally in the hippocampus. We recorded the event-related potentials (ERPs) elicited by the visual and verbal memory encoding and recognition tasks.ResultsP300-like potentials were recorded in the hippocampus by visual and verbal memory encoding and recognition tasks and in the ANT by the visual encoding and visual and verbal recognition tasks. No significant ERPs were recorded during the verbal encoding task in the ANT. In the visual and verbal recognition tasks, the P300-like potentials in the ANT preceded the P300-like potentials in the hippocampus.ConclusionsThe ANT is a structure in the memory pathway that processes memory information before the hippocampus. We suggest that the ANT has a specific role in memory processes, especially memory recognition, and that memory disturbance should be considered in patients with ANT-DBS and in patients with ANT lesions.ANT is well positioned to serve as a subcortical gate for memory processing in cortical structures.

Anomalous single‐subject based morphological cortical networks in drug‐naive, first‐episode major depressive disorder

“…These findings are in line with previous studies showing higher white matter connection strength among cortical-subcortical networks in MDD [Long et al, 2015] and GM alteration in related regions Wise et al, 2016]. The neocortex-striatum-thalamus-cerebellum circuitry may contribute to altered regulation of emotion and cognition in mood disorders [Bostan et al, 2013;Buckner, 2013;Guo et al, 2015;Price and Drevets, 2012], while the thalamohippocampal circuitry might be more specifically related to memory disturbances in depression [Price and Drevets, 2009;Stillova et al, 2015]. The neocortex-striatum-thalamus-cerebellum circuitry may contribute to altered regulation of emotion and cognition in mood disorders [Bostan et al, 2013;Buckner, 2013;Guo et al, 2015;Price and Drevets, 2012], while the thalamohippocampal circuitry might be more specifically related to memory disturbances in depression [Price and Drevets, 2009;Stillova et al, 2015].…”

“…Thalamocortical functional dysconnectivity was also observed in psychotic disorders and related to cognitive impairment [Lui et al, 2014;Woodward and Heckers, 2015]. The neocortex-striatum-thalamus-cerebellum circuitry may contribute to altered regulation of emotion and cognition in mood disorders [Bostan et al, 2013;Buckner, 2013;Guo et al, 2015;Price and Drevets, 2012], while the thalamohippocampal circuitry might be more specifically related to memory disturbances in depression [Price and Drevets, 2009;Stillova et al, 2015].…”

Neural correlates of visual memory in patients with diffuse axonal injury

“…These regions have been associated with attentional processing, an important element of memory encoding [16,17,21]. We also found a negative correlation between the volume of white matter of several subcortical structures and the performance in this task, in line with recent studies showing the involvement of subcortical structures in memory functioning [86][87][88]. Finally, the volume of grey matter of the rolandic operculum and the fusiform gyrus were associated with PAL performance in accordance with the role of these structures in somatosensory processing [12,13,18,89].…”

Spectral organization of focal seizures within the thalamotemporal network

“…The motivation for studying the ANT stems from preclinical studies that demonstrated its ability to regulate seizure onset and propagation in mesial temporal lobe seizure, thereby potentially making ANT a clinically relevant target in TLE . Furthermore, the ANT is integral to the limbic circuit that regulates neurobehavioral functions, including memory, mood, and emotions . It has been shown that open‐loop deep brain stimulation (DBS) of ANT can disrupt these physiological processes and worsen sleep, depression, and memory .…”