Contributions of the ventromedial prefrontal cortex to goal-directed action selection

In this article, it will be argued that one of the key contributions of the ventromedial prefrontal cortex (vmPFC) to goal-directed action selection lies both in retrieving the value of goals that are the putative outcomes of the decision process and in establishing a relative preference ranking for these goals by taking into account the value of each of the different goals under consideration in a given decision-making scenario. These goal-value signals are then suggested to be used as an input into the on-line computation of action values mediated by brain regions outside of the vmPFC, such as parts of the parietal cortex, supplementary motor cortex, and dorsal striatum. Collectively, these areas can be considered to be constituent elements of a multistage decision process whereby the values of different goals must first be represented and ranked before the value of different courses of action available for the pursuit of those goals can be computed

Electrophysiological responses to alcohol cues are not associated with Pavlovian-to-Instrumental Transfer in social drinkers

Peer reviewedPublisher PD

Environmental Effects On Drosophila Brain Development And Learning

Brain development and behavior are sensitive to a variety of environmental influences including social interactions and physicochemical stressors. Sensory input in situ is a mosaic of both enrichment and stress, yet little is known about how multiple environmental factors interact to affect brain anatomical structures, circuits and cognitive function. In this study, we addressed these issues by testing the individual and combined effects of sub-adult thermal stress, larval density and early-adult living spatial enrichment on brain anatomy and olfactory associative learning in adult Drosophila melanogaster. In response to heat stress, the mushroom bodies (MBs) were the most volumetrically impaired among all of the brain structures, an effect highly correlated with reduced odor learning performance. However, MBs were not sensitive to either larval culture density or early-adult living conditions. Extreme larval crowding reduced the volume of the antennal lobes, optic lobes and central complex. Neither larval crowding nor early-adult spatial enrichment affected olfactory learning. These results illustrate that various brain structures react differently to environmental inputs, and that MB development and learning are highly sensitive to certain stressors (pre-adult hyperthermia) and resistant to others (larval crowding). © 2018. Published by The Company of Biologists Ltd

A Java simulator of Rescorla and Wagner's prediction error model and configural cue extensions

In this paper we present the “R&W Simulator” (version 3.0), a Java simulator of Rescorla and Wagner's prediction error model of learning. It is able to run whole experimental designs, and compute and display the associative values of elemental and compound stimuli simultaneously, as well as use extra configural cues in generating compound values; it also permits change of the US parameters across phases. The simulator produces both numerical and graphical outputs, and includes a functionality to export the results to a data processor spreadsheet. It is user-friendly, and built with a graphical interface designed to allow neuroscience researchers to input the data in their own “language”. It is a cross-platform simulator, so it does not require any special equipment, operative system or support program, and does not need installation. The “R&W Simulator” (version 3.0) is available free

A GABAergic projection from the centromedial nuclei of the amygdala to ventromedial prefrontal cortex modulates reward behavior

The neural circuitry underlying mammalian reward behaviors involves several distinct nuclei throughout the brain. It is widely accepted that the midbrain dopamine (DA) neurons are critical for the reward-related behaviors. Recent studies have shown that the centromedial nucleus of the amygdala (CeMA) has a distinct role in regulating reward-related behaviors. However, the CeMA and ventromedial PFC (vmPFC) interaction in reward regulation remains poorly understood. Here, we identify and dissect a GABAergic projection that originates in the CeMA and terminates in the vmPFC (VGat-Cre(CeMA-vmPFC)) using viral-vector-mediated, cell-type-specific optogenetic techniques in mice. Pathway-specific optogenetic activation of the VGat-Cre(CeMA-vmPFC) circuit in awake, behaving animals produced a positive, reward-like phenotype in real-time place preference and increased locomotor activity in open-field testing. In sucrose operant conditioning, the photoactivation of these terminals increased nose-poking effort with no effect on licking behavior and robustly facilitated the extinction of operant behavior. However, photoactivation of these terminals did not induce self-stimulation in the absence of an external reward. The results described here suggest that the VGat-Cre(CeMA-vmPFC) projection acts to modulate existing reward-related behaviors. SIGNIFICANCE STATEMENT Many studies have shown that the interactions between the centromedial nucleus of the amygdala (CeMA) and ventromedial PFC (vmPFC) have critical roles for emotional regulation. However, most studies have associated this circuit with fear and anxiety behaviors and emphasized top-down processing from vmPFC to CeMA. Here, we provide new evidence for bottom-up CeMA to vmPFC influence on reward-related behaviors. Although previous work implicated the CeMA in incentive salience, our results isolate the investigation to a specific CeMA GABAergic projection to the vmPFC. This long-range GABAergic interaction between amygdala and frontal cortex adds a new dimension to the complex regulation of reward-related behaviors