The mediodorsal nucleus of the thalamus (MD), with its extensive connections to the lateral pFC, has been implicated in human working memory and executive functions. However, this understanding is based solely on indirect evidence from human lesion and imaging studies and animal studies. Direct, causal evidence from humans is missing. To obtain direct evidence for MD's role in humans, we studied patients treated with deep brain stimulation (DBS) for refractory epilepsy. This treatment is thought to prevent the generalization of a seizure by disrupting the functioning of the patient's anterior nuclei of the thalamus (ANT) with high-frequency electric stimulation. This structure is located superior and anterior to MD, and when the DBS lead is implanted in ANT, tip contacts of the lead typically penetrate through ANT into the adjoining MD. To study the role of MD in human executive functions and working memory, we periodically disrupted and recovered MD's function with high-frequency electric stimulation using DBS contacts reaching MD while participants performed a cognitive task engaging several aspects of executive functions. We hypothesized that the efficacy of executive functions, specifically working memory, is impaired when the functioning of MD is perturbed by high-frequency stimulation. Eight participants treated with ANT-DBS for refractory epilepsy performed a computer-based test of executive functions while DBS was repeatedly switched ON and OFF at MD and at the control location (ANT). In comparison to stimulation of the control location, when MD was stimulated, participants committed 2.26 times more errors in general (total errors; OR = 2.26, 95% CI [1.69, 3.01]) and 2.86 times more working memory-related errors specifically (incorrect button presses; OR = 2.88, CI [1.95, 4.24]). Similarly, participants committed 1.81 more errors in general ( OR = 1.81, CI [1.45, 2.24]) and 2.08 times more working memory-related errors ( OR = 2.08, CI [1.57, 2.75]) in comparison to no stimulation condition. "Total errors" is a composite score consisting of basic error types and was mostly driven by working memory-related errors. The facts that MD and a control location, ANT, are only few millimeters away from each other and that their stimulation produces very different results highlight the location-specific effect of DBS rather than regionally unspecific general effect. In conclusion, disrupting and recovering MD's function with high-frequency electric stimulation modulated participants' online working memory performance providing causal, in vivo evidence from humans for the role of MD in human working memory.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1162/jocn_a_01176 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Research on the evolution of college online public opinion risk based on improved Grey Wolf Optimizer combined with LSTM model.
PLoS One
January 2025
School of Marxism, Central South University, Changsha, China.
Since the dissemination of information is more rapid and the scale of users on online platforms is enormous, the public opinion risk is more visible and harder to tackle for universities and authorities. Improving the accuracy of predictions regarding online public opinion crises, especially those related to campuses, is crucial for maintaining social stability. This research proposes a public opinion crisis prediction model that applies the Grey Wolf Optimizer (GWO) algorithm combined with long short-term memory (LSTM) and implements it to analyze a trending topic on Sina Weibo to validate its prediction accuracy.
View Article and Find Full Text PDFRepresentational geometry explains puzzling error distributions in behavioral tasks.
Proc Natl Acad Sci U S A
January 2025
Department of Economics, Columbia University, New York, NY 10027.
Measuring and interpreting errors in behavioral tasks is critical for understanding cognition. Conventional wisdom assumes that encoding/decoding errors for continuous variables in behavioral tasks should naturally have Gaussian distributions, so that deviations from normality in the empirical data indicate the presence of more complex sources of noise. This line of reasoning has been central for prior research on working memory.
View Article and Find Full Text PDFDeciphering the Neural Effects of Emotional, Motivational, and Cognitive Challenges on Inhibitory Control Processes.
Hum Brain Mapp
February 2025
Department of Psychological and Brain Sciences, University of Delaware, Newark, Delaware, USA.
Converging lines of research indicate that inhibitory control is likely to be compromised in contexts that place competing demands on emotional, motivational, and cognitive systems, potentially leading to damaging impulsive behavior. The objective of this study was to identify the neural impact of three challenging contexts that typically compromise self-regulation and weaken impulse control. Participants included 66 healthy adults (M/SD = 29.
View Article and Find Full Text PDFSemantic similarity is not emotional: No effect of similarity defined by valence, arousal, and dominance on short-term ordered recall.
Mem Cognit
January 2025
École de Psychologie, Université de Moncton, Moncton, NB, E1A 3E9, Canada.
In short-term ordered recall tasks, phonological similarity impedes item and order recall, while semantic similarity benefits item recall with a weak or null effect on order recall. Ishiguro and Saito recently suggested that these contradictory findings were due to an inadequate assessment of semantic similarity. They proposed a novel measure of semantic similarity based on the distance between items in a three-dimensional space composed of the semantic dimensions of valence, arousal, and dominance.
View Article and Find Full Text PDFThe molecular mechanism of nitric oxide in memory consolidation and its role in the pathogenesis of memory-related disorders.
Neurogenetics
January 2025
Department of Surgery, Surgical Research Section, Hamad Medical Corporation, Doha, Qatar.
Memory is a dynamic process of encoding, storing, and retrieving information. It includes sensory, short-term, and long-term memory, each with unique characteristics. Nitric oxide (NO) is a biological messenger synthesized on demand by neuronal nitric oxide synthase (nNOS) through a biochemical process initiated by glutamate binding to NMDA receptors, causing membrane depolarization and calcium influx.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!