Adaptive coding of stimuli is well documented in perception, where it supports efficient encoding over a broad range of possible percepts. Recently, a similar neural mechanism has been reported also in value-based decision, where it allows optimal encoding of vast ranges of values in PFC: neuronal response to value depends on the choice context (relative coding), rather than being invariant across contexts (absolute coding). Additionally, value learning is sensitive to the amount of feedback information: providing complete feedback (both obtained and forgone outcomes) instead of partial feedback (only obtained outcome) improves learning. However, it is unclear whether relative coding occurs in all PFC regions and how it is affected by feedback information. We systematically investigated univariate and multivariate feedback encoding in various mPFC regions and compared three modes of neural coding: absolute, partially-adaptive and fully-adaptive.

Twenty-eight human participants (both sexes) performed a learning task while undergoing fMRI scanning. On each trial, they chose between two symbols associated with a certain outcome. Then, the decision outcome was revealed. Notably, in one-half of the trials participants received partial feedback, whereas in the other half they got complete feedback. We used univariate and multivariate analysis to explore value encoding in different feedback conditions.

We found that both obtained and forgone outcomes were encoded in mPFC, but with opposite sign in its ventral and dorsal subdivisions. Moreover, we showed that increasing feedback information induced a switch from absolute to relative coding. Our results suggest that complete feedback information enhances context-dependent outcome encoding.

SIGNIFICANCE STATEMENT This study offers a systematic investigation of the effect of the amount of feedback information (partial vs complete) on univariate and multivariate outcome value encoding, within multiple regions in mPFC and cingulate cortex that are critical for value-based decisions and behavioral adaptation. Moreover, we provide the first comparison of three possible models of neural coding (i.e., absolute, partially-adaptive, and fully-adaptive coding) of value signal in these regions, by using commensurable measures of prediction accuracy. Taken together, our results help build a more comprehensive picture of how the human brain encodes and processes outcome value. In particular, our results suggest that simultaneous presentation of obtained and foregone outcomes promotes relative value representation.

The PFC, through its high degree of interconnectivity with cortical and subcortical brain areas, mediates cognitive and emotional processes in support of adaptive behaviors. This includes the formation of fear memories when the anticipation of threat demands learning about temporal or contextual cues, as in trace fear conditioning. In this variant of fear learning, the association of a cue and shock across an empty trace interval of several seconds requires sustained cue-elicited firing in the prelimbic cortex (PL). However, it is unknown how and when distinct PL afferents contribute to different associative components of memory. Among the prominent inputs to PL, the hippocampus shares with PL a role in both working memory and contextual processing. Here we tested the necessity of direct hippocampal input to the PL for the acquisition of trace-cued fear memory and the simultaneously acquired contextual fear association. Optogenetic silencing of ventral hippocampal (VH) terminals in the PL of adult male Long-Evans rats selectively during paired trials revealed that direct communication between the VH and PL during training is necessary for contextual fear memory, but not for trace-cued fear acquisition. The pattern of the contextual memory deficit and the disruption of local PL firing during optogenetic silencing of VH-PL suggest that the VH continuously updates the PL with the current contextual state of the animal, which, when disrupted during memory acquisition, is detrimental to the subsequent rapid retrieval of aversive contextual associations.

SIGNIFICANCE STATEMENT Learning to anticipate threat from available contextual and discrete cues is crucial for survival. The prelimbic cortex is required for forming fear memories when temporal or contextual complexity is involved, as in trace fear conditioning. However, the respective contribution of distinct prelimbic afferents to the temporal and contextual components of memory is not known. We report that direct input from the ventral hippocampus enables the formation of the contextual, but not trace-cued, fear memory necessary for the subsequent rapid expression of a fear response. This finding dissociates the contextual and working-memory contributions of prelimbic cortex to the formation of a fear memory and demonstrates the crucial role for hippocampal input in contextual fear learning.

Phototransduction in Drosophila is mediated by phospholipase C (PLC) and Ca²⁺-permeable TRP channels, but the function of endoplasmic reticulum (ER) Ca²⁺ stores in this important model for Ca²⁺ signaling remains obscure. We therefore expressed a low affinity Ca²⁺ indicator (ER-GCaMP6-150) in the ER, and measured its fluorescence both in dissociated ommatidia and in vivo from intact flies of both sexes. Blue excitation light induced a rapid (tau ~0.8 s), PLC-dependent decrease in fluorescence, representing depletion of ER Ca²⁺ stores, followed by a slower decay, typically reaching ~50% of initial dark-adapted levels, with significant depletion occurring under natural levels of illumination. The ER stores refilled in the dark within 100–200 s. Both rapid and slow store depletion were largely unaffected in InsP₃ receptor mutants, but were much reduced in trp mutants. Strikingly, rapid (but not slow) depletion of ER stores was blocked by removing external Na⁺ and in mutants of the Na⁺/Ca²⁺ exchanger, CalX, which we immuno-localized to ER membranes in addition to its established localization in the plasma membrane. Conversely, overexpression of calx greatly enhanced rapid depletion. These results indicate that rapid store depletion is mediated by Na⁺/Ca²⁺ exchange across the ER membrane induced by Na⁺ influx via the light-sensitive channels. Although too slow to be involved in channel activation, this Na⁺/Ca²⁺ exchange-dependent release explains the decades-old observation of a light-induced rise in cytosolic Ca²⁺ in photoreceptors exposed to Ca²⁺-free solutions.

SIGNIFICANCE STATEMENT Phototransduction in Drosophila is mediated by phospholipase C, which activates TRP cation channels by an unknown mechanism. Despite much speculation, it is unknown whether endoplasmic reticulum (ER) Ca²⁺ stores play any role. We therefore engineered flies expressing a genetically encoded Ca²⁺ indicator in the photoreceptor ER. Although NCX Na⁺/Ca²⁺ exchangers are classically believed to operate only at the plasma membrane, we demonstrate a rapid light-induced depletion of ER Ca²⁺ stores mediated by Na⁺/Ca²⁺ exchange across the ER membrane. This NCX-dependent release was too slow to be involved in channel activation, but explains the decades-old observation of a light-induced rise in cytosolic Ca²⁺ in photoreceptors bathed in Ca²⁺-free solutions.

Priming refers to the influence that a previously encountered object exerts on future responses to similar objects. For many years, visual priming has been known as a facilitation and sometimes an inhibition effect that lasts for an extended period of time. It contrasts with the recent finding of an oscillated priming effect where facilitation and inhibition alternate over time periodically. Here we developed a computational model of visual priming that combines rhythmic sampling of the environment (attentional oscillation) with active preparation for future events (temporal expectation). Counterintuitively, it shows that both the sustained and oscillated priming effects can emerge from an interaction between attentional oscillation and temporal expectation. The interaction also leads to novel predictions, such as the change of visual priming effects with temporal expectation and attentional oscillation. Reanalysis of two published datasets and the results of two new experiments of visual priming tasks with male and female human participants provide support for the model's relevance to human behavior. More generally, our model offers a new perspective that may unify the increasing findings of behavioral and neural oscillations with the classic findings in visual perception and attention.

SIGNIFICANCE STATEMENT There is increasing behavioral and neural evidence that visual attention is a periodic process that sequentially samples different alternatives in the theta frequency range. It contrasts with the classic findings of sustained facilitatory or inhibitory attention effects. How can an oscillatory perceptual process give rise to sustained attention effects? Here we make this connection by proposing a computational model for a "fruit fly" visual priming task and showing both the sustained and oscillated priming effects can have the same origin: an interaction between rhythmic sampling of the environment and active preparation for future events. One unique contribution of our model is to predict how temporal contexts affects priming. It also opens up the possibility of reinterpreting other attention-related classic phenomena.

As an important cognitive bias, the framing effect shows that our decision preferences are sensitive to the verbal description (i.e., frame) of options. This study focuses on the neural underpinnings of the social framing effect, which is based on decision-making regarding other people. A novel paradigm was used in which participants made a trade-off between economic benefits and the feelings of others. This decision was described as either a "harm" to, or "not helping," other persons in two conditions (Harm frame vs Help frame). Both human males and females were recruited. Participants behaved more prosocially for Harm frame compared with Help frame, resulting in a significant social framing effect. Using functional magnetic resonance imaging, Experiment 1 showed that the social framing effect was associated with stronger activation in the temporoparietal junction (TPJ), especially its right part. The functional connectivity between the right TPJ (rTPJ) and medial prefrontal cortex predicted the social framing effect on the group level. In Experiment 2, we used transcranial direct current stimulation to modulate the activity of the rTPJ and found that the social framing effect became more prominent under anodal (excitatory) stimulation, while the nonsocial framing effect elicited by the economic gain/loss gambling frame remained unaffected. The rTPJ results might be associated with moral conflicts modulated by the social consequences of an action or different levels of mentalizing with others under different frame conditions, but alternative interpretations are also worth noting. These findings could help elucidate the psychological mechanisms of the social framing effect.

SIGNIFICANCE STATEMENT Previous studies have suggested that the framing effect is generated from an interaction between the amygdala and anterior cingulate cortex. This opinion, however, is based on findings from nonsocial framing tasks. Recent research has highlighted the importance of distinguishing between the social and nonsocial framing effects. The current study focuses on the social framing effect and finds out that the temporoparietal junction and its functional connectivity with the medial prefrontal cortex play a significant role. Additionally, modulating the activity of this region leads to changes in social (but not nonsocial) framing effect. Broadly speaking, these findings help understand the difference in neural mechanisms between social and nonsocial decision-making. Meanwhile, they might be illuminating to promote helping behavior in society.

Today leading international experts on climate change, the IPCC, presented their latest report on the impacts of climate change on humanity, and what we can do about it. It’s a lengthy report, so we’ve shrunk it down to Oxfam's five key takeaways on climate change and hunger. 1. Climate change: the impacts on crops are worse than we thought Climate change has [...]

In its simplest form, a kitchen garden produces fresh fruits, vegetables and herbs for delicious, healthy meals. Research suggests that kitchen gardens can supply up to half of all non-staple food needs, as well as a significant number of vitamins and minerals. This makes them an invaluable tool for food security in vulnerable communities. ‘Imagine one day you lost everything you owned.  [...]

The photos below were entries in the XIV World Forestry Congress ‘Forests and People’ photo contest. Take a tour with us around the world and learn interesting facts on forests and the socioeconomic benefits they provide to people around the world. 

Paseano Gómez López is a farmer from Nuevo Sonora, Chiapas state, Mexico. He grows corn and chili peppers. But to cultivate fields, farmers need money to buy supplies. They are often forced to take loans at high interest rates (10-20 percent). Sometimes, the farm’s yields don’t even cover the costs and they fall into debt. Farmers in Mexico are also battling with poor [...]

Women and children, especially pregnant women and children 0-2 years of age, are among the groups most vulnerable to food insecurity and chronic malnutrition. This is no different in Mozambique where, according to the FAO Technical Secretariat for Food Security and Nutrition 35% of the population is food insecure and 43% of children under 5 are chronically malnourished. Chronic undernutrition levels [...]

More with less. This is the challenge and the mantra for our future. There will be many more of us in the years to come. We will go from a population of 7.6 billion today to 9.8 billion in 2050; yet, with our current rate of usage, there will be less fresh water, less arable soil, less available land for [...]

Where would you find the world’s largest recreation center and the most natural supermarket? Forests wouldn’t have been your first answer, would it? That’s the thing about forests. They keep secrets.

Times like this have led us to rethink our daily lives, from our basic everyday habits to the way we usually get information. FAO is working to guarantee continued [...]

These parks are less popular, but no less spectacular

A digital-savvy historian discusses his popular @HistOpinion Twitter account

It's June 1945 and the USS Barb has just launched an unprecedented attack on the factories of the Japanese island of Shari

Wildfires leave behind a patchwork of forest densities that can give bats more room to fly and hunt

The snails are an invasive crop pest that are known to eat more than just coffee rust

A new simulation points to a previously untold chapter in Titan’s history

A collection of 14 restored wooden statues, including a two-ton William IV, will be shown at the Box Museum in England

The burial site, which contains remains from both the Picts and the Norse, is at risk of disappearing due to coastal erosion

After 85 years, officials plan to remove the old, undetonated bombs that were part of a 1935 plan to divert lava flow on Mauna Loa

Together, the paintings—including one by Anthony van Dyck—could be worth around £10 million if sold on the open market

Greenery is sprouting from scorched tree trunks as the forests regrow their canopies

The suspects were found drunk and hiding under a tarpaulin, reportedly in possession of small stones from the fire-ravaged cathedral

Thieves pilfered "The Parsonage Garden at Nuenen in Spring 1884" from the Singer Laren in the early hours of Monday morning

Audible's new service is aimed at school-age children participating in distance learning but features selections likely to appeal to all

Though not as plentiful as the Perseids in summer, the Lyrids can serve up some serious fireballs

The two NASA astronauts will lift off from historic launch pad 39A, used for the Apollo and space shuttle missions

The story behind the image, and its removal, led to mixed reactions from the public, including native communities

The London institution's online offerings include 280,000 newly added Creative Commons images

The simultaneous mating calls of the male pug-nosed tree frog confuses bats but not female frogs

The app features a database of some two million artworks housed at more than 120 venues

Narrated by Smithsonian Distinguished Scholar Richard Kurin, the 24-part video series blends history with modern mainstays

How do you select one image to represent half a century of photography and art? You don’t

Tulips, cherry blossoms and orchids supply a ray of hope during self-isolation

A Smithsonian folklorist examines Jewish humor in the midst of a pandemic

These virtual versions of classic and lesser-known games are ideal for social distancing

These paintings, sculptures and illustrations honor the bonds of motherhood

Browse the collections for artworks with a CC0 license as part of the Smithsonian's Open Access Initiative,

Tour a gallery of presidential portraits, print a 3-D model of a fossil or volunteer to transcribe historical documents

From virtual museum tours to space exploration, ancient worlds and natural phenomena, this hub has you covered

Henny Sundig is a pivotal figure in the history of WWII Danish resistance. In 1943, aged just 19, she risked it all to make a daring journey in her boat, Gerda III, to rescue as many Jews as she could.

Henry Ford spent the majority of the war as a pacifist. By 1917, however, his state-of-the-art assembly line was churning out vital engine parts to feed the war machine.

Veteran musher Lance Mackey has had his 21st place finish in this year's Iditarod Trail Sled Dog Race vacated because of a failed drug test, race officials announced Thursday.

In this protocol, DNA fragments are separated according to size by electrophoresis through low-melting-temperature agarose, and then recovered by melting the agarose and extracting with phenol:chloroform. The protocol works best for DNA fragments ranging in size from 0.5 to 5.0 kb. Yields of DNA fragments outside this range are usually lower, but often are sufficient for many purposes.

Amid widespread sell-offs in risky asset classes, corporate bond exchange-traded funds (ETFs) traded at steep discounts to underlying asset values in March. Contributing factors were high market volatility, reduced risk-taking by dealers and investors' reaction to policy decisions. Policy interventions that improve market functioning in a given sector can have temporary yet important spillovers to other segments through portfolio rebalancing by investors.

Open for visitors, these houses model upcycling at its finest

British product designer Lucy Hughes has invented a biodegradable plastic made from fish offcuts

A woman who lost her sister to COVID-19 at the start of the month is thanking the staff at Northwood who took "excellent" care of her in her final days. Jean Harrigan, 90, is being remembered for her caring and lively nature.