In demanding listening situations, a listener's motivational state may affect their cognitive investment. Here, we aim to delineate how domain-specific sensory processing, domain-general neural alpha power, and pupil size as a proxy for cognitive investment encode influences of motivational state under demanding listening. Participants (male and female) performed an auditory gap-detection task while the pupil size and the magnetoencephalogram were simultaneously recorded. Task demand and a listener's motivational state were orthogonally manipulated through changes in gap duration and monetary-reward prospect, respectively. Whereas task difficulty impaired performance, reward prospect enhanced it. The pupil size reliably indicated the modulatory impact of an individual's motivational state. At the neural level, the motivational state did not affect auditory sensory processing directly but impacted attentional postprocessing of an auditory event as reflected in the late evoked-response field and alpha-power change. Both pregap pupil dilation and higher parietal alpha power predicted better performance at the single-trial level. The current data support a framework wherein the motivational state acts as an attentional top–down neural means of postprocessing the auditory input in challenging listening situations.

Aggression involves both sexually monomorphic and dimorphic actions. How the brain implements these two types of actions is poorly understood. We found that in Drosophila melanogaster, a set of neurons, which we call CL062, previously shown to mediate male aggression also mediate female aggression. These neurons elicit aggression acutely and without the presence of a target. Although the same set of actions is elicited in males and females, the overall behavior is sexually dimorphic. The CL062 neurons do not express fruitless, a gene required for sexual dimorphism in flies, and expressed by most other neurons important for controlling fly aggression. Connectomic analysis in a female electron microscopy dataset suggests that these neurons have limited connections with fruitless expressing neurons that have been shown to be important for aggression and signal to different descending neurons. Thus, CL062 is part of a monomorphic circuit for aggression that functions parallel to the known dimorphic circuits.

Key event-related potentials (ERPs) of perceptual decision-making such as centroparietal positivity (CPP) elucidate how evidence is accumulated toward a given choice. Furthermore, this accumulation can be impacted by visual target selection signals such as the N2 contralateral (N2c). How these underlying neural mechanisms of perceptual decision-making are influenced by the spatial congruence of distractors relative to target stimuli remains unclear. Here, we used electroencephalography (EEG) in humans of both sexes to investigate the effect of distractor spatial congruency (same vs different hemifield relative to targets) on perceptual decision-making. We confirmed that responses for perceptual decisions were slower for spatially incongruent versus congruent distractors of high salience. Similarly, markers of target selection (N2c peak amplitude) and evidence accumulation (CPP slope) were found to be lower when distractors were spatially incongruent versus congruent. To evaluate the effects of congruency further, we applied drift diffusion modeling to participant responses, which showed that larger amplitudes of both ERPs were correlated with shorter nondecision times when considering the effect of congruency. The modeling also suggested that congruency's effect on behavior occurred prior to and during evidence accumulation when considering the effects of the N2c peak and CPP slope. These findings point to spatially incongruent distractors, relative to congruent distractors, influencing decisions as early as the initial sensory processing phase and then continuing to exert an effect as evidence is accumulated throughout the decision-making process. Overall, our findings highlight how key electrophysiological signals of perceptual decision-making are influenced by the spatial congruence of target and distractor.

Impaired inhibitory synapse development is suggested to drive neuronal hyperactivity in autism spectrum disorders (ASD) and epilepsy. We propose a novel mechanism by which astrocytes control the development of parvalbumin (PV)-specific inhibitory synapses in the hippocampus, implicating ephrin-B/EphB signaling. Here, we utilize genetic approaches to assess functional and structural connectivity between PV and pyramidal cells (PCs) through whole-cell patch–clamp electrophysiology, optogenetics, immunohistochemical analysis, and behaviors in male and female mice. While inhibitory synapse development is adversely affected by PV-specific expression of EphB2, a strong candidate ASD risk gene, astrocytic ephrin-B1 facilitates PV->PC connectivity through a mechanism involving EphB signaling in PV boutons. In contrast, the loss of astrocytic ephrin-B1 reduces PV->PC connectivity and inhibition, resulting in increased seizure susceptibility and an ASD-like phenotype. Our findings underscore the crucial role of astrocytes in regulating inhibitory circuit development and discover a new role of EphB2 receptors in PV-specific inhibitory synapse development.

In a new book, a curator at England's Natural History Museum describes rare and interesting nests and eggs—from the house sparrow to the village weaver—and the lessons they hold for avian conservation

A new book reveals striking images from six decades of the beloved Wildlife Photographer of the Year competition

Tens of thousands of farmers are bringing in their first rice harvest just six months after one of the worst typhoons to ever hit the Philippines left their fields in [...]

On Friday, 7 December during the 160th session of the Council, a side event on the Africa Solidarity Trust [...]

Read the series on how FAO increased efficiency, effectiveness and transparency to better support its Members in the transformation of agrifood systems.

Christopher Gray | Smithsonian Magazine’s 2016 American Ingenuity Award Winner for Youth Achievement Christopher Gray is the founder and CEO of Scholly, the groundbreaking web and mobile app that matches current or future college students who need financial support with scholarships that can help them. Scholly has been downloaded 850,000 times and has connected college students with some $50 million in scholarships. Philadelphia-based Gray, an ABC “Shark Tank” winner and recipient of a $100,000 grant from philanthropist Steve Case’s Rise of the Rest competition, sees his digital platform as a 21st-century tool for helping countless young Americans achieve their college dreams without piling on crushing debt.

Building captive colonies for eventual re-introduction to the wild, scientists from Atlanta rescue endangered frogs and other amphibians threatened with extinction by a fatal fungus spreading through South American forests

Our host, Eric Schulze explains how 1 + 1 = 0 when it comes to sound

Transitions: Photographs by Robert Creamer

Selected by William Coupon for our special issue, this up-and-coming photographer discusses her work

Koshik, an elephant in a South Korean zoo, learned to say five different Korean words (Still: iStock/ROMAOSLO)

The city famous for blues and barbecue is a little “ragged around the edges” according to tour guide Tad Pierson, who drives tourists around in his pink 1955 Cadillac by Lucian Perkins

In this one-minute video, our Ask Smithsonian Host, Eric Schulze, weighs in on whether or not elephants can jump.

Bull elephant Kevin, crazed with testosterone, challenges Greg, the most powerful elephant in the group

A museum in Portland, Oregon highlights the multi-layered path of 3D imagery, from stereoscopes of the American West to blockbuster movies

Use #physnobel on Twitter to submit your questions. The 2014 Nobel Prize in Physics will be announced on Tuesday, October 7. Join guests Charles Day of Physics Today, Andrew Grant of Science News, Jennifer Ouellette of Cocktail Party Physics and Amanda Yoho of Starts With A Bang! as they discuss predictions for possible winners. Who are the best contenders, and who are the potential "dark horse" candidates? Which major physics finds of this year might stand a shot at a win in the future? Victoria Jaggard and Helen Thompson of Smithsonian.com will be your hosts for the event. Tune in on October 2, and submit your questions on Twitter. Charles Day is the Online Editor for Physics Today magazine. Follow him on Twitter @CSRDay Andrew Grant is the physics reporter for Science News magazine. Follow him on Twitter @sci_grant Jennifer Ouellette is a science writer and blogger at Cocktail Party Physics. Follow her on Twitter @JenLucPiquant Amanda Yoho is a graduate student in theoretical and computational cosmology at Case Western Reserve University and a blogger at Starts With A Bang! Follow her on Twitter @mandaYoho Victoria Jaggard is the science editor for Smithsonian.com. Follow her on Twitter @vmjaggard99 Helen Thompson is a science reporter for Smithsonian.com. Follow her on Twitter @wwrfd

How can something like a tiny, harmless spider or a clown make your heart race and your palms sweat? And for the love of all things science, how can you make these fears stop? Find out in this one-minute video, where Ask Smithsonian host Eric Schulze delves deep into the dark recesses of our minds to get at the facts behind our phobias.

Collector Nakki Goranin leads a tour of her collection (Kenneth Fletcher). Read more at http://smithsonian.com/photobooth

A close look reveals how the famed photographer altered his glass negatives, creating the popular image of Native Americans that still exists today

Smithsonian magazine commissioned Drew Gardner for a project that connects Black Americans today to their lost ancestry. Read about Gardner’s project and process, as well as more details about the subjects of this incredible series here: https://www.smithsonianmag.com/history/descendants-black-civil-war-heroes-wear-heritage-pride-180983397/ Video produced by Sierra Theobald. Special thanks to Drew Gardner Additional credits: Emma MacBeath, WikiTree US Black Heritage project; Ottawa Goodman, research and coordinator; Sam Dole, Penumbra Foundation; Elizabeth Zuck, set design; Calvin Osbourne, props and costume; Angela Huff, hair and make up; Diego Huerta, Lexia Krebs, behind-the-scenes filming; background prints by Fujifilm USA

The act of dive bombing during World War II was a death defying trial of skill and nerve. You aimed your plane down, four miles above the ocean and plummeted at speeds of up to 275 miles per hour

Researchers at a conservation center in Thailand tested many variables to study an elephant’s gait and how they accelerate when facing danger

Deep in the jungles of Brazil, photographer Steve Winter explains how he managed to capture stunning images of one of the world's top predators. Read more about jaguars at http://www.smithsonianmag.com/video/Photographing-the-Elusive-Jaguar.html

Read more about elephants at http://www.smithsonianmag.com/science-nature/How-Male-Elephants-Bond.html Keepers and pachyderms alike are enjoying the new Asian elephant exhibit, Elephant Trails, at the National Zoo.

See how researchers at Smithsonian's National Zoo are trying to glean insight into elephant foraging behavior and more.

Document Deep Dive: http://j.mp/SUXoTF How the Emancipation Proclamation Came to Be Signed: http://j.mp/12q5SE0 What did it take to pull together a draft of the Emancipation Proclamation, Lincoln's inkwell and his pen?

After reviewing more than 30,000 photos, the editors of Smithsonian magazine are proud to announce the winning submissions. Learn more about the finalists and winners of 2024 here: https://www.smithsonianmag.com/arts-culture/see-winners-21st-annual-smithsonian-magazine-photo-contest-180984001/. --- For more videos from Smithsonian Magazine: https://www.smithsonianmag.com/videos/ Digital Editorial Director: Brian Wolly Supervising Producer & Scriptwriter: Michelle Mehrtens Video Editor: Sierra Theobald

Local Burmese fisher Maung Lay shows how his family has traditionally teamed up with rare river dolphins and explains why their partnership is now at risk. (Video by Demelza Stokes and Mark Scialla)

"OK Go made music videos relevant again." – Stephen Colbert OK Go​, Damian Kulash Jr. and Trish Sie​ won the Smithsonian magazine​ American Ingenuity Award for Visual Arts for pushing the music-video envelope with their zero-gravity video for "Upside Down & Inside Out." Read more about their work and see the video here: http://smithmag.co/HZ8vzr The Smithsonian has been celebrating innovation in American culture for more than 150 years, and following in this tradition, Smithsonian magazine presents the American Ingenuity Awards, honoring revolutionary breakthroughs in the arts and sciences, education and social progress. http://smithmag.co/R7hyRO

Credit: Cade Martin / © & ™ Lucasfilm Ltd

Smithsonian magazine commissioned Drew Gardner for a project that connects Black Americans today to their lost ancestry. Read about Gardner’s project and process, as well as more details about the subjects of this incredible series here: https://www.smithsonianmag.com/history/descendants-black-civil-war-heroes-wear-heritage-pride-180983397/ Video produced by Sierra Theobald. Special thanks to Drew Gardner Additional credits: Emma MacBeath, WikiTree US Black Heritage project; Ottawa Goodman, research and coordinator; Sam Dole, Penumbra Foundation; Elizabeth Zuck, set design; Calvin Osbourne, props and costume; Angela Huff, hair and make up; Diego Huerta, Lexia Krebs, behind-the-scenes filming; background prints by Fujifilm USA

The National Gallery of Art organized a comprehensive exhibit of Robert Frank's work (Images courtesy of: National Gallery of Art; Produced by: Diane Bolz and Brian Wolly)

Not to worry—shut-eye comes easily to these aquatic mammals

In the years before digital cameras, the process of getting shots from the field to the printers was incredibly complicated and dangerous. Video by Adam Grossman | Good Dog Media

Read more at http://www.smithsonianmag.com/arts-culture/Herman-Leonards-Eye-for-Jazz.html With just a camera as his ticket, Herman Leonard captured jazz icons performing on and off stage.

The team at the Ol Pejeta Conservancy needs to transport Kinani, a blind male elephant, to a 4,000-acre compound where he'll be able to roam freely without disturbing other wildlife. Weighing in at nearly eight tons, it'll take careful maneuvering and custom equipment to bring the animal to his new sanctuary.

After reviewing more than 30,000 photos, the editors of Smithsonian Magazine are proud to announce the Grand Prize Winner. #shorts

Autodesk vice president Brian Mathews talks with the NASA science communicator about the search for life on other planets and why it’s important

In a telephone interview, Gregory Crewdson remarks on the genesis and production of some of the photos included in the story

Read more at http://www.smithsonianmag.com/specialsections/womens-history/The-Writers-Eye.html Scholars and friends of Eudora Welty discuss how her hobby influenced her later works.

After his start capturing the horrors of the Civil War for Mathew Brady's studio, 19th century photographer Timothy O'Sullivan uncovered the beauty of the great expanses of the American west

Read more at http://www.smithsonianmag.com/history-archaeology/We-Have-Liftoff.html Photographer David Burnett focused his camera on the many tourists who flocked to Florida in 1969 to watch the launch of Apollo 11 (Produced by Molly Roberts; Photographs by David Burnett/Contact Press Images).

Cardiac MRI of an animal that has undergone photosynthetic therapy. CREDIT: Stanford University School of Medicine, Department of Cardiothoracic Surgery

Read more at http://www.smithsonianmag.com/arts-culture/In-Vogue.html At 62 years old, Edward Steichen convinced the U.S. Navy to let him gather a team of photographers to capture the men serving their country in the Pacific Ocean during World War II.

"They have given mankind a completely new way of looking at the universe." – Stephen Hawking, congratulates Kip Thorne, Rainer Weiss, Barry Barish and Ronald Drever, the first scientists to detect gravitational waves. | Smithsonian magazine #IngenuityAwards The Smithsonian has been celebrating innovation in American culture for more than 150 years, and following in this tradition, Smithsonian magazine presents the American Ingenuity Awards, honoring revolutionary breakthroughs in the arts and sciences, education and social progress.