Panic buying has been rife amid the global spread of the new coronavirus, with consumers around the world stockpiling goods like hand sanitizer, canned foods and toilet paper. The trend has seen stores ration products, with U.K. retailers limiting sales of hand hygiene products while Australian shoppers have seen restrictions on the amount of toilet paper they can buy. Psychologists spoke to CNBC to weigh in on why our brains push us to panic buy — even when authorities are assuring the public there's no need to. According to Paul Marsden, a consumer psychologist at the University of the Arts London, the short answer can be found in the psychology of "retail therapy" — where we buy to manage our emotional state. "It's about 'taking back control' in a world where you feel out of control," he said. "More generally, panic buying can be understood as playing to our three fundamental psychology needs."

Those needs were autonomy, or a need for control, relatedness, which Marsden defined as "we shopping" rather than "me shopping," and competence, which is achieved when making a purchase gives people a sense that they are "smart shoppers."

'Fear contagion'

Meanwhile, Sander van der Linden, an assistant professor of social psychology at Cambridge University, said there were both generalized and coronavirus-specific factors at play. "In the U.S., people are receiving conflicting messages from the CDC and the Trump administration," he said. "When one organization is saying it's urgent and another says it's under control, it makes people worry." President Donald Trump downplayed the impact of the U.S. coronavirus outbreak on Twitter this week, with a disconnect reportedly widening between the administration and U.S. health authorities. The virus is now present in at least 35 states, according to the Centers for Disease Control and Prevention (CDC). More generally, a "fear contagion" phenomenon was taking hold, van der Linden added.

"When people are stressed their reason is hampered, so they look at what other people are doing. If others are stockpiling it leads you to engage in the same behavior," he said. "People see photos of empty shelves and regardless of whether it's rational it sends a signal to them that it's the thing to do." "Sometimes there can be a lot of value in social knowledge — from an evolutionary perspective when we don't know how to react to something, we look to others for guidance," he added. "If you're in the jungle and someone jumps away from a snake you automatically do the same thing. But sometimes that gets highjacked and you're told to do something that's not the right thing to do." While sales of hand soaps and sanitizers have soared in markets around the world since the outbreak began, consumers have also been stocking up on a somewhat surprising item – toilet paper. According to Dimitrios Tsivrikos, lecturer in consumer and business psychology at University College London, toilet paper has become an "icon" of mass panic. "In times of uncertainty, people enter a panic zone that makes them irrational and completely neurotic," he said in a phone call. "In other disaster conditions like a flood, we can prepare because we know how many supplies we need, but we have a virus now we know nothing about." "When you enter a supermarket, you're looking for value and high volumes," he added, noting that people are drawn to the large packaging that toilet paper comes in when they are looking to regain a sense of control. Tsivrikos, like van der Linden, told CNBC the lack of a clear voice from authority figures was fueling the panic.