Articles in 2011

This study examines the contribution of a specific phosphatidylinositol 3-kinase (PI3K) isoform, namely PI3Kγ, to hippocampal synaptic plasticity and behavior. The authors find that the loss of PI3Kγ can specifically impair NMDA receptor–mediated long-term depression and cognitive functions that rely on behavioral flexibility.

The authors find that the Avpr1a gene, encoding the vasopressin-1A receptor, is responsible for strain-dependent pain sensitivity of mice to formalin and capsaicin. In humans, a single nucleotide polymorphism in AVPR1A was found to affect capsaicin pain and desmopressin analgesia. In both species, the effects were male specific and dependent on stress levels at the time of testing.

The authors show that synapses between rod bipolar cells and AII amacrine cells in the retina can encode luminance and compute contrast in the sustained and transient components of vesicle release, respectively. A release/replenishment model shows that a single, homogenous pool of vesicles is sufficient to generate this behavior.

The authors generated knock-in mice of the AMPAR auxiliary subunit TARP that lack the C-terminal PDZ ligand. They found that synaptic transmission and AMPAR were reduced without changes in extrasynaptic AMPAR expression, but LTP was unaltered.

Using two-photon microscopy in mice, the authors find that the number of cortical spines increases in adolescent mice while they are awake and decreases while they are asleep.

Maturation of adult-born neurons in the dentate gyrus is known to require GABAergic input. Here the authors show that a subtype of interneurons, namely neurogliaform cells, acts as the primary source of GABA for newborn neurons in mouse dentate gyrus.

The authors studied the dynamic regulation of Ca²⁺-permeable AMPARs (CP-AMPARs) in oligodendrocyte precursor cells. Group 1 mGluRs regulate CP-AMPARs via a pathway that requires intracellular Ca²⁺, PI3 kinase, PICK-1 and JNK. Purinergic receptor activation decreases CP-AMPAR expression.

This study reports that people are worse at incorporating negative information when updating their beliefs. Correspondingly, neural activity encodes desirable information updates, but there is weaker encoding of unexpectedly undesirable information.

Examining the role of ephrin-B3 in dendritic and synaptic development in vivo, this study finds that ephrin-B3 functions postsynaptically as a receptor to initiate reverse signaling events that organize dendritic branching complexity, spine maturation and formation of functional synapses.

The authors examine the neural circuitry causally involved in normative, fairness-related decisions by generating a temporarily diminished capacity for costly normative behavior through non-invasive brain stimulation. Their findings suggest that a prefrontal network, the activation of rDLPFC and pVMPFC and the connectivity between them, facilitates costly normative decisions.

Cocaine can easily cross the placental and fetal blood-brain barrier, and in utero exposure to cocaine can cause lasting behavioral changes in postnatal periods. Here, Bellone et al. studied the physiological and circuit level mechanism behind the consequence of in utero cocaine exposure and found a postnatal synaptic maturation defect of excitatory input to the dopaminergic neurons in the ventral tegmental area of mice. In particular, they found that late embryonic in utero cocaine exposure causes a delay in AMPAR/NMDAR switch in early postnatal mouse brain.

We can efficiently and rapidly recognize daily-life visual settings. A study finds that scene recognition involves the posterior object-selective visual cortex, where multiple within-scene objects are represented in parallel.

A study finds that recall of fear-provoking memory changes the surface levels of AMPA receptors in the dorsal hippocampus. Inhibition of AMPA receptor trafficking strengthens the memory and results in excessive fear.

Engrailed, a homeobox transcription factor that is crucial for neuronal development, is now shown to regulate mitochondrial complex I and to be critical for the survival, protection and physiology of adult dopamine neurons.

Few brain regions' functions have been debated as intensely as those of the dorsal anterior cingulate cortex. A computational model now suggests that seemingly diverse cingulate responses may be explained by a single construct, 'negative surprise', which occurs when actions do not produce the expected outcome.

Using hemisphere-specific optogenetic activation of hippocampal fibers, this study finds that the magnitude of long-term potentiation in CA1 neurons depends on whether afferents originate in left or right CA3.

This study shows that lesioning a rat's amygdala affects only familiarity-based recognition, having no effect on recollection-based recognition, and further dissociates the role of medial temporal lobe structures mediating recognition memory.

One mechanism by which medial prefontal cortex (mPFC) exerts cognitive control is thought to involve the subthalamic nucleus (STN), which acts as a temporary brake on behavior. Here the authors found increases in mPFC and STN theta power as a function of decision conflict. Increases in mPFC theta power predicted increased decision thresholds. STN deep brain stimulation reversed this relationship, resulting in impulsive choice.