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“This study examined age differences in performance monitoring during learning of a stimulus-response association task. At the beginning of the learning process, amplitudes of the response-locked error-related negativity (ERN or Ne) and correct response-related negativity (CRN) did not differ in both age groups. With advanced learning the response ERN/Ne increased and the CRN decreased in younger adults, but did not dissociate in older adults. Feedback ERN amplitudes decreased with learning in both age groups and were reduced in older relative to younger adults.
Results indicate that performance monitoring became error specific this website with advanced learning in younger adults, but not in older adults. This might be due to weak representations of stimulus-response mappings in older adults as they learned worse. The decrease of the feedback ERN with learning and aging might suggest a decline of attention paid to negative feedback.”
“Astrocytes in the somatosensory ventrobasal (VB) thalamus of rats respond to glutamatergic synaptic input with metabotropic glutamate receptor (mGluR) mediated intracellular calcium ([Ca2+](i)) elevations. Astrocytes in the VB
thalamus also release the gliotransmitter (GT) glutamate in a Ca2+-dependent manner. The tripartite find more synapse hypothesis posits that astrocytic [Ca2+](i) elevations resulting from synaptic input releases gliotransmitters that then feedback to modify the synapse. Understanding the dynamics of this process and the conditions under which it occurs are therefore important steps in elucidating the potential roles
and impact of GT release in particular brain activities. In this study, we investigated the relationship between VB thalamus afferent synaptic input and astrocytic glutamate release EPZ015666 order by recording N-methyl-D-aspartate (NMDA) receptor-mediated slow inward currents (SICs) elicited in neighboring neurons. We found that Lemniscal or cortical afferent stimulation, which can elicit astrocytic [Ca2+](i) elevations, do not typically result in the generation of SICs in thalamocortical (TC) neurons. Rather, we find that the spontaneous emergence of SICs is largely resistant to acute afferent input. The frequency of SICs, however, is correlated to long-lasting afferent activity. In contrast to short-term stimulus-evoked GT release effects reported in other brain areas, astrocytes in the VB thalamus do not express a straightforward input-output relationship for SIC generation but exhibit integrative characteristics. (C) 2012 IBRO. Published by Elsevier Ltd. All rights reserved.”
“Gene density and orientation of genes in eukaryotes seem to be correlated with the replication origin and the mutation rate is greater in late replicating regions; however, the reason for these patterns is unknown.