COVID-19's long-term effects on the brain are causing concern among scientists -- among them, Dr. Adam Hampshire. He is a cognitive neuroscientist at Imperial College London. Hampshire's latest research, published in The Lancet medical journal, associates coronavirus with a decrease in reasoning and problem solving abilities. He breaks down his findings.

Lieutenant Colonel Alexander Vindman rose to prominence when he testified to Congress in 2019 about the now infamous phone call between President Donald Trump and Ukrainian leader Volodymyr Zelensky. Vindman's account of the incident was at the heart of President Trump's first impeachment and his emotive testimony had a major impact. He reflects on this in his new book.

The Delta variant is surging as vaccination rates slow to a crawl in some states. James Brainard is the Mayor of Carmel in the Republican stronghold of Indiana. While the state's vaccination numbers are far behind those of many states, the city of Carmel is way ahead with about 80% of residents fully vaccinated. What's behind this success story? Mayor Brainard joins Bianna to discuss.

This week marks the 56th anniversary of America's Voting Rights Act signed by President Johnson. This landmark legislation is now under assault. At least 18 states have enacted laws restricting ballot access. Joining the show are historian Doris Kearns Goodwin, who once worked for LBJ and is the author of "No Ordinary Time;" and Julia Sweig, who wrote a biography of LBJ’s secret weapon: his wife.

Iran finds itself at its own crossroads. A new hardline president takes office tomorrow. Talks to revive the nuclear deal seem to be on life support. And today Israel blamed an Iranian commander for a deadly drone attack on an oil tanker. Journalist Robin Wright breaks all this down.

The deadly port explosion was one of the largest non-nuclear blasts in history, sparked by dangerous chemicals sitting neglected for years. More than 200 people were killed, thousands were injured, and countless others bear the invisible wounds inflamed by unanswered questions and the lack of accountability. Georges Kettaneh joins Christiane from Beirut.

The state of Louisiana is experiencing its worst COVID-19 surge yet, with an all-time high in hospitalizations. Democratic Governor John Bel Edwards has reinstated mask mandates in an effort to combat infections. And here he is talking to our Walter Isaacson about wrestling with the COVID-19 crisis and what good government can do.

California Governor Gavin Newsom faces a rare recall election this September and is trying to rally . In addition to COVID spiking in the state again, he's dealing with contentious debates over mask mandates, raging wildfires, and drought plaguing nearly half the state. A lot to talk about with the Chief Executive of America's most populous state. He joins Christiane from Sacramento.

Robin D'Angelo is famed for her bestselling book "White Fragility." D'Angelo's work aims to educate white progressives on the part they play within a racist culture. It's a theme she continues in her new book "Nice Racism." Here she is explaining her work and the criticism that has been leveled against her to Michel Martin.

President-Elect Ebrahim Raisi was officially accepted by Iran's Supreme leader Ayatollah Ali Khamenei ahead of Thursday's inauguration. Raisi is a much more hardline and anti-western politician than the outgoing president Hassan Rouhani. Correspondent Fred Pleitgen takes a look at what's top of Raisi's to-do list and gives an update on the nuclear deal.

This summer, we've seen extreme weather spread everywhere. Turkey is one of the latest countries to be hit where at least 8 people have died in more than 100 wildfires in the last week. We are witnessing the slow destruction of the natural world -- an issue highlighted by the award-winning Turkish-British novelist Elif Shafak in her latest book, "The Island of Missing Trees."

Only half the U.S. population is fully vaccinated. The Federal government is trying to raise vaccine enthusiasm with treats and perks. "What if the unvaccinated can’t be persuaded?" is the title of Ezra Klein's latest column for the New York Times. He joins Christiane from California.

A recent internal document from the CDC reveals that it's as contagious as chickenpox and it carries an increased risk of severe illness and hospitalization. Michael Osterholm is the Director for Infectious Disease, Research and Policy at the University of Minnesota. He speaks with our Walter Isaacson about how the U.S. should respond and what can be learned from other countries.

There have been dramatic developments at the Olympics. Belarusian sprinter Krystina Tsimanouskaya was at the Polish Embassy today, speaking about political asylum. Another big story is Simone Biles, who is returning to compete. Correspondent Selina Wang is on the ground in Tokyo and speaks to Christiane.

In France, President Macron is putting pressure on the holdouts with a tough 'no dose, no fun' approach -- banning the unvaccinated from theatres, restaurants and cinemas. The tough-love approach seems to be working. Nathalie Loiseau, French member of European Parliament, joins the program to discuss her country's policies.

Saad Mohseni heads the biggest media organization in Afghanistan, the Moby Media Group, which includes Tolo TV. His latest article for the digital newsletter Air Mail, "The View from Here," gives a stark warning of what Afghans stand to lose if the Taliban seize power. He joins Bianna from Greece.

Imagine writing a memoir detailing the last days of your parents' lives. Now imagine that one of your parents is the late literary giant and Nobel laureate Gabriel García Márquez. Rodrigo García joins Bianna to discuss his creative process and his new book, "A Farewell to Gabo and Mercedes."

The Delta variant is surging in the U.S. and around the world, and it's even more troubling than was first thought. That's according to an internal document from the CDC. The public health agency now believes the strain is as contagious as the chickenpox. Dr. Reed Tuckson joins the program to unpack this news.

Over 100 CEOs have come together to form the organization CEO Action for Racial Equity. Its goal: addressing systemic racism and creating lasting change through public policy. The CEO of this initiative, Roy Weathers, and Denny's CEO John Miller are determined not to let politics stand in their way. They speak with Hari Sreenivasan about their plan.

After days of uncertainty, an important act of diplomacy has finally taken place, as announced to the world on President Biden’s Twitter feed. Biden posted a photograph of his meeting with Belarus’s opposition leader, Svetlana Tikhanovskaya, saying he was honored to meet with her at the White House. Tikhanovskaya has been touring the U.S. to raise awareness of her people’s struggle for democracy.