Medical and Biomedical Researches

Octopus Conditioning: A Multi-Armed Approach to the LTP-Learning Question.

June 28th, 2008
Octopus Conditioning: A Multi-Armed Approach to the LTP-Learning Question. A recent study shows that avoidance conditioning in the cephalopod Octopus vulgaris is mediated by long-term potentiation (LTP), a form of synaptic plasticity thought to be important in vertebrate associative learning. Thus, LTP appears to be an ...

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Neurobiology: venom of wasps and initiation of movements.

June 28th, 2008
Neurobiology: venom of wasps and initiation of movements. The ability to initiate movements can be impaired in some brain injuries even though motor actions proceed normally once they are begun. The effects of venom that wasps use in preying upon cockroaches could provide insights into this ...

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Social Cognition: Hi There! Here’s Something Interesting.

June 28th, 2008
Social Cognition: Hi There! Here\'s Something Interesting. A new study of gaze following shows that human infants are highly sensitive to the communicative intent of the person they are interacting with. Frith CD. Wellcome Trust Centre for Neuroimaging at University College London, 12 Queen Square, ...

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Phagocytic Signaling: You Can Touch, but You Can’t Eat.

June 28th, 2008
Phagocytic Signaling: You Can Touch, but You Can\'t Eat. The ability of phagocytes to discriminate between viable/healthy and apoptotic/foreign/abnormal cells is of fundamental importance; a recent study provides new molecular insights into the function of CD47-SIRPalpha signaling in this discrimination. Kinchen JM, Ravichandran KS. Beirne ...

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Multisensory Integration: A Late Bloomer.

June 28th, 2008
Multisensory Integration: A Late Bloomer. Under many circumstances, human adults integrate information from different sensory modalities, such as vision and hearing, in a statistically optimal fashion. New results suggest that optimal multisensory integration only develops in middle childhood. Ernst MO. Max Planck Institute for Biological ...

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Diatom Signalling: Deadly Messages.

June 28th, 2008
Diatom Signalling: Deadly Messages. How are populations of phytoplankton in the oceans regulated? Recent studies are revealing the presence of complex cell-cell and intracellular signalling mechanisms that can lead to growth regulation and even programmed cell death in response to abiotic stress and biotic interactions. Brownlee C. ...

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Task-irrelevant learning occurs only when the irrelevant feature is weak.

June 28th, 2008
Task-irrelevant learning occurs only when the irrelevant feature is weak. The role of attention in perceptual learning has been controversial. Numerous studies have reported that learning does not occur on stimulus features that are irrelevant to a subject\'s task [1,2] and have concluded that focused attention ...

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Rapid increase in fish numbers follows creation of world’s largest marine reserve network.

June 28th, 2008
Rapid increase in fish numbers follows creation of world\'s largest marine reserve network. No-take marine reserves (NTMRs) are much advocated as a solution to managing marine ecosystems, protecting exploited species and restoring natural states of biodiversity [1,2]. Increasingly, it is becoming clear that effective marine conservation ...

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Crocodile egg sounds signal hatching time.

June 28th, 2008
Crocodile egg sounds signal hatching time. Crocodilians are known to vocalize within the egg shortly before hatching [1,2]. Although a possible function of these calls - inducing hatching in siblings and stimulating the adult female to open the nest - has already been suggested, it has ...

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The origin of the myelination program in vertebrates.

June 28th, 2008
The origin of the myelination program in vertebrates. The myelin sheath was a transformative vertebrate acquisition, enabling great increases in impulse propagation velocity along axons. Not all vertebrates possess myelinated axons, however, and when myelin first appeared in the vertebrate lineage is an important open question. ...

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Striatal activity underlies novelty-based choice in humans.

June 28th, 2008
Striatal activity underlies novelty-based choice in humans. The desire to seek new and unfamiliar experiences is a fundamental behavioral tendency in humans and other species. In economic decision making, novelty seeking is often rational, insofar as uncertain options may prove valuable and advantageous in the long ...

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Cooperative nonlinearities in auditory cortical neurons.

June 28th, 2008
Cooperative nonlinearities in auditory cortical neurons. Cortical receptive fields represent the signal preferences of sensory neurons. Receptive fields are thought to provide a representation of sensory experience from which the cerebral cortex may make interpretations. While it is essential to determine a neuron\'s receptive field, it ...

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Organizing principles of spectro-temporal encoding in the avian primary auditory area field L.

June 28th, 2008
Organizing principles of spectro-temporal encoding in the avian primary auditory area field L. The organization of postthalamic auditory areas remains unclear in many respects. Using a stimulus based on properties of natural sounds, we mapped spectro-temporal receptive fields (STRFs) of neurons in the primary auditory area ...

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Synapse-specific adaptations to inactivity in hippocampal circuits achieve homeostatic gain control

June 28th, 2008
Synapse-specific adaptations to inactivity in hippocampal circuits achieve homeostatic gain control while dampening network reverberation. Synaptic homeostasis, induced by chronic changes in neuronal activity, is well studied in cultured neurons, but not in more physiological networks where distinct synaptic circuits are preserved. We characterized inactivity-induced adaptations ...

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Perisomatic GABA release and thalamocortical integration onto neocortical excitatory cells are regul

June 28th, 2008
Perisomatic GABA release and thalamocortical integration onto neocortical excitatory cells are regulated by neuromodulators. Neuromodulators such as acetylcholine, serotonin, and noradrenaline are powerful regulators of neocortical activity. Although it is well established that cortical inhibition is the target of these modulations, little is known about their ...

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Coupling of neural activity to blood flow in olfactory glomeruli is mediated by astrocytic pathways.

June 28th, 2008
Coupling of neural activity to blood flow in olfactory glomeruli is mediated by astrocytic pathways. Functional neuroimaging uses activity-dependent changes in cerebral blood flow to map brain activity, but the contributions of presynaptic and postsynaptic activity are incompletely understood, as are the underlying cellular pathways. Using ...

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DAG lipase activity is necessary for TRP channel regulation in Drosophila photoreceptors.

June 28th, 2008
DAG lipase activity is necessary for TRP channel regulation in Drosophila photoreceptors. In Drosophila, a phospholipase C-mediated signaling cascade links photoexcitation of rhodopsin to the opening of the TRP/TRPL channels. A lipid product of the cascade, diacylglycerol (DAG) and its metabolite(s), polyunsaturated fatty acids (PUFAs), have ...

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Mechanism of Ca2+ disruption in Alzheimer’s disease by presenilin regulation of InsP(3) receptor ch

June 28th, 2008
Mechanism of Ca2+ disruption in Alzheimer\'s disease by presenilin regulation of InsP(3) receptor channel gating. Mutations in presenilins (PS) are the major cause of familial Alzheimer\'s disease (FAD) and have been associated with calcium (Ca2+) signaling abnormalities. Here, we demonstrate that FAD mutant PS1 (M146L)and PS2 ...

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Alternative translation initiation in rat brain yields K(2P)2.1 potassium channels permeable to sodi

June 28th, 2008
Alternative translation initiation in rat brain yields K(2P)2.1 potassium channels permeable to sodium. K(2P) channels mediate potassium background currents essential to central nervous system function, controlling excitability by stabilizing membrane potential below firing threshold and expediting repolarization. Here, we show that alternative translation initiation (ATI) regulates ...

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A precisely timed asynchronous pattern of ON and OFF retinal ganglion cell activity during propagati

June 28th, 2008
A precisely timed asynchronous pattern of ON and OFF retinal ganglion cell activity during propagation of retinal waves. Patterns of coordinated spontaneous activity have been proposed to guide circuit refinement in many parts of the developing nervous system. It is unclear, however, how such patterns, which ...

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Glioma stem cells: a midterm exam.

June 28th, 2008
Glioma stem cells: a midterm exam. Several years ago, the discovery of a highly tumorigenic subpopulation of stem-like cells embedded within fresh surgical isolates of malignant gliomas lent support to a new paradigm in cancer biology--the cancer stem cell hypothesis. At the same time, these \"glioma ...

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Characterizing auditory receptive fields.

June 28th, 2008
Characterizing auditory receptive fields. In this issue of Neuron, two papers by Atencio et al. and Nagel and Doupe adapt new computational methods to map the spectrotemporal response fields of neurons in the auditory cortex. The papers take different but complementary approaches to apply theoretical techniques ...

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The olfactory glomerulus: a model for neuro-glio-vascular biology.

June 28th, 2008
The olfactory glomerulus: a model for neuro-glio-vascular biology. The cellular basis of brain imaging is emerging as a new frontier in current neuroscience. In this issue of Neuron, Petzold et al. analyze a model system, the olfactory glomerulus, to show how neurovascular coupling involves an elaborate ...

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In search of the holy grail for Drosophila TRP.

June 28th, 2008
In search of the holy grail for Drosophila TRP. Activation of the archetypal Transient Receptor Potential (TRP) channel, which is essential for Drosophila phototransduction, depends on a phospholipase C (PLC). However, the precise mechanism linking PLC to the gating of TRP has been elusive. In this ...

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Thrilling moment of an inhibitory channel.

June 28th, 2008
Thrilling moment of an inhibitory channel. Long thought to be potassium channels with calming influence quietly working away in the background, in this issue of Neuron, Thomas et al. demonstrate that K(2P)2.1 (TREK-1) channels have two endogenous isoforms due to a mechanism called alternative translation initiation ...

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