A new function of offset response in the primate auditory cortex: marker of temporal integration.

Offset responses are traditionally viewed as indicators of sound cessation. Here, we investigate offset responses to auditory click trains, examining how they are modulated by inter-click intervals (ICIs) and train duration. Using extracellular recordings and electrocorticography (ECoG) in non-human primates, alongside electroencephalography (EEG) in humans, we show that offset responses are significantly influenced by both ICI and train length, thereby establishing them as markers of temporal integration.

Neural correlates of novelty detection in the primary auditory cortex of behaving monkeys.

The neural mechanisms underlying novelty detection are not well understood, especially in relation to behavior. Here, we present single-unit responses from the primary auditory cortex (A1) from two monkeys trained to detect deviant tones amid repetitive ones. Results show that monkeys can detect deviant sounds, and there is a strong correlation between late neuronal responses (250-350 ms after deviant onset) and the monkeys' perceptual decisions.

Stimulus-specific adaptation (SSA) in the auditory system: Functional relevance and underlying mechanisms.

Rapid detection of novel stimuli that appear suddenly in the surrounding environment is crucial for an animal's survival. Stimulus-specific adaptation (SSA) may be an important mechanism underlying novelty detection. In this review, we discuss the latest advances in SSA research by addressing four main aspects: 1) the frequency dependence of SSA and the origin of SSA in the auditory cortex: 2) spatial SSA and its comparison with frequency SSA: 3) feature integration in SSA and its implications in novelty detection: 4) functional significance and the physiological mechanism of SSA.

Cross-Modal Interaction and Integration Through Stimulus-Specific Adaptation in the Thalamic Reticular Nucleus of Rats.

Stimulus-specific adaptation (SSA), defined as a decrease in responses to a common stimulus that only partially generalizes to other rare stimuli, is a widespread phenomenon in the brain that is believed to be related to novelty detection. Although cross-modal sensory processing is also a widespread phenomenon, the interaction between the two phenomena is not well understood. In this study, the thalamic reticular nucleus (TRN), which is regarded as a hub of the attentional system that contains multi-modal neurons, was investigated.

Adaptation in the Dorsal Belt and Core Regions of the Auditory Cortex in the Awake Rat.

The rat auditory cortex is divided anatomically into several areas, but little is known about the functional differences in information processing among these areas. Three tonotopically organized core fields, namely, the primary (A1), anterior (AAF), and ventral (VAF) auditory fields, as well as one non-tonotopically organized belt field, the dorsal belt (DB), were identified based on their response properties. Compared to neurons in A1, AAF and VAF, units in the DB exhibited little or no response to pure tones but strong responses to white noise.

Stress Resistance Screen in a Human Primary Cell Line Identifies Small Molecules That Affect Aging Pathways and Extend ' Lifespan.

Increased resistance to environmental stress at the cellular level is correlated with the longevity of long-lived mutants and wild-animal species. Moreover, in experimental organisms, screens for increased stress resistance have yielded mutants that are long-lived. To find entry points for small molecules that might extend healthy longevity in humans, we screened ∼100,000 small molecules in a human primary-fibroblast cell line and identified a set that increased oxidative-stress resistance.

Integrative stimulus-specific adaptation of the natural sounds in the auditory cortex of the awake rat.

Using oddball stimulus with pure tones, researchers have extensively investigated stimulus-specific adaptation (SSA), which has been regarded as a method of novelty detection, from the inferior colliculus (IC) to the auditory cortex (AC). However, until now, it is not clear whether SSA is preserved for natural sounds or whether it exists for spatial cues in the AC. Moreover, it is also unclear whether SSA integrates different types of cues within a single modality such as sound location and sound identity.

Frequency-Dependent Stimulus-Specific Adaptation and Regularity Sensitivity in the Rat Auditory Thalamus.

Recent electrophysiological studies in animals using oddball stimuli have demonstrated that neurons along the auditory pathway from the inferior colliculus to the auditory cortex (AC) have a strong response to rarely presented stimuli. This phenomenon is termed stimulus-specific adaptation (SSA), which is regarded as novelty detection. However, in the medial geniculate body (MGB), it is not clear whether SSA is frequency dependent or if neurons in the MGB are sensitive to the regularity of the stimuli.

Adaptation facilitates spatial discrimination for deviant locations in the thalamic reticular nucleus of the rat.

The capacity to identify unanticipated abnormal cues in a natural scene is vital for animal survival. Stimulus-specific adaptation (SSA) has been considered the neuronal correlate for deviance detection. There have been comprehensive assessments of SSA in the frequency domain along the ascending auditory pathway, but only little attention given to deviance detection in the spatial domain.

Intrinsically de-sialylated CD103(+) CD8 T cells mediate beneficial anti-glioma immune responses.

Background: Cancer vaccines reproducibly cure laboratory animals and reveal encouraging trends in brain tumor (glioma) patients. Identifying parameters governing beneficial vaccine-induced responses may lead to the improvement of glioma immunotherapies. CD103(+) CD8 T cells dominate post-vaccine responses in human glioma patients for unknown reasons, but may be related to recent thymic emigrant (RTE) status.

Distribution of nanoparticles throughout the cerebral cortex of rodents and non-human primates: Implications for gene and drug therapy.

When nanoparticles/proteins are infused into the brain, they are often transported to distal sites in a manner that is dependent both on the characteristics of the infusate and the region targeted. We have previously shown that adeno-associated virus (AAV) is disseminated within the brain by perivascular flow and also by axonal transport. Perivascular distribution usually does not depend strongly on the nature of the infusate.

T cells enhance stem-like properties and conditional malignancy in gliomas.

Background: Small populations of highly tumorigenic stem-like cells (cancer stem cells; CSCs) can exist within, and uniquely regenerate cancers including malignant brain tumors (gliomas). Many aspects of glioma CSCs (GSCs), however, have been characterized in non-physiological settings.

Methods: We found gene expression similarity superiorly defined glioma "stemness", and revealed that GSC similarity increased with lower tumor grade.