Sequential neural information processing in nidopallium caudolaterale of pigeons during the acquisition process of operant conditioning The avian nidopallium caudolaterale, a key region of information integration and processing, is considered to be playing an important role in operant conditioning acquisition and extinction. To reveal sequential neural information processing in the process, neural signals of different experimental periods (induction, acquisition, and extinction) from the nidopallium caudolaterale of pigeons were acquired and the energy of the specific frequency band was analyzed from the light stimulation input to the pecking action output. We found that during the induction period, the pigeons establish a relationship between the visual cue and decision behavior. The neural coding activities of pecking intention are earlier than that of light stimulation. Moreover, the neural coding activities of pecking intention move forward through strengthening and consolidation of the acquisition period. During the extinction period, the relationship of the visual cue and decision behavior is broken. The coding of light stimulation and pecking intention disappears gradually, and the disappearance of intention coding activities is earlier. The results show that there may be present an elaborate time-course contingency between the light stimulation and the pecking intention in the nidopallium caudolaterale. This study provides the electrophysiological experimental evidence for the dynamic coding mechanism of nidopallium caudolaterale.

The role of long non-coding RNA SNHG12 in neuroprotection following cerebral ischemic injury As one of the major causes of mortality and disability worldwide, ischemic stroke has never been received enough attention. Following ischemia/reperfusion injury, long non-coding RNAs have been extensively found to be involved into inflammatory responses, microvascular endothelial cell death, and angiogenesis in the brain. The small nucleolar RNA host gene 12 was found to be significantly increased following transient middle cerebral artery occlusion. However, the effect and underlying mechanism of small nucleolar RNA host gene 12 in ischemic stroke remain to be explored. We established an oxygen-glucose deprivation/reoxygen in primary neurons model to mimic ischemic stroke. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide assay and lactate dehydrogenase assay were used to prove that knockdown small nucleolar RNA host gene 12 reduced cell viability after oxygen-glucose deprivation/reoxygen treatment. And the western blot showed that knockdown small nucleolar RNA host gene 12 aggravated the oxygen-glucose deprivation/reoxygen-induced apoptosis. What’s more, the pro-inflammatory cytokine level was increased in small nucleolar RNA host gene 12 knockdown primary neurons. Mechanistically, the specific distribution of small nucleolar RNA host gene 12 in primary neurons was detected by fluorescence in situ hybridisation. Additionally, we demonstrate small nucleolar RNA host gene 12 attenuates oxygen-glucose deprivation/reoxygen injury through activating Akt signaling pathway. Therefore, the small nucleolar RNA host gene 12 may be the new potential therapeutic target for the alleviation of cerebral ischemic injury.

Selective impairment of the executive attentional network in adult patients with neurofibromatosis type 1 Cognitive dysfunction accompanied by neurofibromatosis type 1 is one of the significant characteristics of this neurocutaneous disorder and has a serious impact on patients’ quality of life. Although studies on cognitive function in children with neurofibromatosis type 1 have revealed that attentional impairment is a key deficit in these patients, few studies have examined their neuropsychological profile, especially whether the attentional function is also abnormal and specific in adult patients with neurofibromatosis type 1. In this study, we used the revised attention network test to examine the function of three attentional networks–alerting, orienting and executive control–in 20 adult patients with neurofibromatosis type 1 in comparison to 20 normal controls. Adult patients with neurofibromatosis type 1 showed significant greater conflict effect for the executive control network, but no significant differences were found for alerting and orienting network relative to normal controls. These results provide evidence that there is an attentional deficit which is specifically associated with the executive control network in adult patients with neurofibromatosis type 1.

The hypnotic effect of propofol involves inhibition of GABAergic neurons in the lateral hypothalamus Propofol is widely used for induction and maintenance of anaesthesia, which causes a rapid loss of consciousness. So far the mechanisms underlying the effect of propofol are still largely unknown. Here, we found that microinjection of propofol in the lateral hypothalamus caused a significant decrease in wakefulness and an increase in the amount of non-rapid eye movement sleep and rapid eye movement sleep. Application of propofol in the lateral hypothalamus affected the electroencephalogram power spectra with a decrease in theta oscillations and an increase in the delta oscillations. Additionally, using whole-cell patch clamp recording, we found propofol inhibited the excitability of the GABAergic neurons in the lateral hypothalamus, which plays a critical role in controlling wakefulness. Altogether, these findings indicate that propofol targets lateral hypothalamus and generates a hypnotic state, which might involve the inhibition of GABAergic neurons. These results provide a novel mechanism to explain propofol-elicited anaesthesia.

The early stage of face detection in patients with major depressive disorder: an ERP study To investigate whether perceptual processes involved in early stages of face processing are influenced by depressive disorder, the face detection and configural analysis were assessed by recording the N170 component elicited by faces and objects (tables) presented under upright and inverted conditions. The N170 component elicited at occipital–temporal sites by faces was larger and peaked later than that elicited by tables, and inverted faces significantly enhanced and delayed the N170. The N170 in response to faces was enhanced in patients with major depressive disorder and the N170 face effect for upright condition was significantly larger in major depressive disorder patients than that in controls. However, the N170 inversion effect did not differ between two groups. These data indicate that, compared with normal controls, there is abnormal face perception at the early stage of processing faces in major depressive disorder patients but the major depressive disorder patients may have intact configural processing of faces.

Separation effect of early visual cortex V1 under different crowding conditions: a transcranial magnetic stimulation study The visual crowding makes it difficult to identify the patterns in peripheral vision, but the neural mechanism for this phenomenon is still unclear because of different opinions. To study the separation effect of early visual cortex V1 under different crowding conditions, single-pulse transcranial magnetic stimulation (TMS) is applied within the right V1. The experimental design includes two factors: TMS intensity (10%, 65%, and 90% of the phosphene threshold) and crowding conditions (high and low). The accuracy results show that there is a strong interaction between crowding and TMS conditions. When the TMS intensity is 65% or 90% of the phosphene threshold, more crowding will be perceived under the high crowding condition, and less crowding under the low crowding condition. We concluded that the high and the low crowding conditions can be separated by TMS. These results support the assumption that the crowding is related to V1 and occurs in the visual coding phase.

Neuroanatomical correlates of extraversion: a test–retest study implicating gray matter volume in the caudate nucleus Extraversion is a propensity for optimism, positive emotion, and sociability. Many studies have explored the brain correlates of extraversion, and the results have mainly emphasized the role of reward-related brain regions. However, it is unclear whether imaging studies of the brain’s reward system can show good test–retest reliability. We aim to investigate the neuroanatomical correlates of extraversion and to examine the test–retest reliability of the results. Voxel-based morphometry derived from MRI and the Revised NEO Personality Inventory were performed in a sample of 382 subjects (dataset 1), and multiple regression was used to analyze the relation between regional gray matter volume (GMV) and extraversion scores. We found that bilateral GMV in the caudate region was positively associated with extraversion. Two years later, 133 subjects from dataset 1 were re-examined with MRI and the Revised NEO Personality Inventory. A conjunction analysis showed that the body of left caudate nucleus was consistently associated with extraversion. The bilateral GMV of the caudate nucleus, which may be related to sensitivity to rewards, may be a critical brain structure underlying extraverted behavior. This study is the first to use two different time points to assess the consistency of the association of brain structures with extraversion.

Comparison of contrast-dependent phase sensitivity in primary visual cortex of mouse, cat and macaque Neurones in the primary visual cortex (V1) are classified into simple and complex types. Simple cells are phase-sensitive, that is, they modulate their responses according to the position and brightness polarity of edges in their receptive fields. Complex cells are phase invariant, that is, they respond to edges in their receptive fields regardless of location or brightness polarity. Simple and complex cells are quantified by the degree of sensitivity to the spatial phases of drifting sinusoidal gratings. Some V1 complex cells become more phase-sensitive at low contrasts. Here we use a standardized analysis method for data derived from grating stimuli developed for macaques to reanalyse data previously collected from cats, and also collect and analyse the responses of 73 mouse V1 neurons. The analysis provides the first consistent comparative study of contrast-dependent phase sensitivity in V1 of mouse, cat and macaque monkey.

Orexinergic actions modify occurrence of slow inward currents on neurons in the pedunculopontine nucleus Orexins are neuromodulatory peptides of the lateral hypothalamus which regulate homeostatic mechanisms including sleep-wakefulness cycles. Orexinergic actions stabilize wakefulness by acting on the nuclei of the reticular activating system, including the pedunculopontine nucleus. Orexin application to pedunculopontine neurons produces a noisy tonic inward current and an increase in the frequency and amplitudes of excitatory postsynaptic currents. In the present project, we investigated orexinergic neuromodulatory actions on astrocyte-mediated neuronal slow inward currents of pedunculopontine neurons and their relationships with tonic currents by using slice electrophysiology on preparations from mice. We demonstrated that, in contrast to several other neuromodulatory actions and in line with literature data, orexin predominantly elicited a tonic inward current. A subpopulation of the pedunculopontine neurons possessed slow inward currents. Independently from the tonic currents, actions on slow inward currents were also detected, which resembled other neuromodulatory actions: if slow inward currents were almost absent on the neuron, orexin induced an increase of the charge movements by slow inward currents, whereas if slow inward current activity was abundant on the neurons, orexin exerted inhibitory action on it. Our data support the previous findings that orexin elicits only inward currents in contrast with cannabinoid, cholinergic or serotonergic actions. Similar to the aforementioned neuromodulatory actions, orexin influences slow inward currents in a way depending on control slow inward current activity. Furthermore, we found that orexinergic actions on slow inward currents are similarly independent from its actions on tonic currents, as it was previously found with other neuromodulatory agonists.

EphA4 receptor regulates outwardly rectifying chloride channel in CA1 hippocampal neurons after ischemia-reperfusion CA1 hippocampal neurons are sensitive to ischemia. The erythropoietin-producing hepatocellular carcinoma (Eph) receptors are a cell-cell contact signaling pathway for regulating neuron function and death. However, the mechanisms of EphA receptor in neuron death after ischemia remain unclear. In this study, we present evidence that outwardly rectifying chloride channels reside in CA1 hippocampal neurons. EphA4 receptor increased chloride channel currents. Moreover, the EphA4 receptor no longer had significant effects on enhanced channel currents following ischemia-reperfusion. Inhibition of EphA4 receptor with EphA4-Fc significantly decreased the channel currents after ischemia-reperfusion. These results suggest that the increased effect of the EphA4 receptor on the outwardly rectifying chloride channel activity in CA1 hippocampal neurons may provide better treatment for ischemic brain injury.