An increase in the deoxygenated hemoglobin concentration induced by a working memory task during the refractory period in the hemodynamic response in the human cerebral cortex

2020 ◽  
Vol 714 ◽  
pp. 134531
Author(s):  
Kenji Nakamura ◽  
Yuuki Shiroto ◽  
Yuuki Tamura ◽  
Keisuke Koyama ◽  
Kengo Takeuchi ◽  
...  
2021 ◽  
Vol 15 ◽  
Author(s):  
Stephen Grossberg

All perceptual and cognitive circuits in the human cerebral cortex are organized into layers. Specializations of a canonical laminar network of bottom-up, horizontal, and top-down pathways carry out multiple kinds of biological intelligence across different neocortical areas. This article describes what this canonical network is and notes that it can support processes as different as 3D vision and figure-ground perception; attentive category learning and decision-making; speech perception; and cognitive working memory (WM), planning, and prediction. These processes take place within and between multiple parallel cortical streams that obey computationally complementary laws. The interstream interactions that are needed to overcome these complementary deficiencies mix cell properties so thoroughly that some authors have noted the difficulty of determining what exactly constitutes a cortical stream and the differences between streams. The models summarized herein explain how these complementary properties arise, and how their interstream interactions overcome their computational deficiencies to support effective goal-oriented behaviors.


2020 ◽  
Author(s):  
Yasuki Noguchi ◽  
Ryusuke Kakigi

AbstractVisual working memory (vWM) is an important ability required for various cognitive tasks although its neural underpinnings remain controversial. While many studies have focused on theta (4-7 Hz) and gamma (> 30 Hz) rhythms as a substrate of vWM, here we show that temporal signals embedded in alpha (8-12 Hz) and beta (13-30 Hz) bands can be a good predictor of vWM capacity. Neural activity of healthy human participants was recorded with magnetoencephalography when they performed a classical vWM task (change detection). We analyzed changes in inter-peak intervals (IPIs) of oscillatory signals along with an increase in WM load (a number of to-be-memorized items, 1-6). Results showed a load-dependent reduction of IPIs in the parietal and frontal regions, indicating that alpha/beta rhythms became faster when multiple items were stored in vWM. Furthermore, this reduction in IPIs was positively correlated with individual vWM capacity, especially in the frontal cortex. Those results indicate that vWM is represented as a change in oscillation frequency in the human cerebral cortex.


NeuroImage ◽  
2009 ◽  
Vol 47 ◽  
pp. S139
Author(s):  
J Szczepanik ◽  
C Martin-Soelch ◽  
K Barhaghi ◽  
S Fromm ◽  
W Drevets

2008 ◽  
Author(s):  
Alexandra S. Atkins ◽  
Marc G. Berman ◽  
John Jonides ◽  
Patricia A. Reuterlorenz

2020 ◽  
Vol 75 (3) ◽  
pp. 226-233
Author(s):  
Svetlana P. Sergeeva ◽  
Aleksey V. Lyundup ◽  
Valery V. Beregovykh ◽  
Petr F. Litvitskiy ◽  
Aleksey A. Savin ◽  
...  

Background. The search for protein (these include c-fos, ERK1/2, MAP2, NOTCH1) expression that provide neuroplasticity mechanisms of the cerebral cortex after ischemic stroke (IS) patterns is an urgent task. Aims to reveal c-fos, ERK1/2, MAP2, NOTCH1 proteins expression patterns in human cerebral cortex neurons after IS. Materials and methods. We studied 9 left middle cerebral artery (LMCA) IS patients cerebral cortex samples from 3 zones: 1 the zone adjacent to the necrotic tissue focus; 2 zone remote from the previous one by 47 cm; 3 zone of the contralateral hemisphere, symmetric to the IS focus. Control samples were obtained from 3 accident died people. Identification of targeted proteins NSE, c-fos, ERK1/2, MAP2, NOTCH1 was performed by indirect immunoperoxidase immunohistochemical method. Results. Moving away from the ischemic focus, there is an increase in the density of neurons and a decrease in the damaged neurons proportion, the largest share of c-fos protein positive neurons in zone 2, NOTCH1 positive neurons in zone 1, smaller fractions of ERK1/2 and MAP2 positive neurons compared to the control only in samples of zone 1. Conclusions. With the IS development, the contralateral hemisphere is intact tissue increased activation zone, while the zones 1 and 2 have pathological activation signs. In zone 1 of the range, the adaptive response of the tissue decreases, and in zone 2 it expands. Therefore, a key target for therapeutic intervention is zone 2.


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