Eurasian Jays: Exploring the Fascinating World of Avian 'Mental Time Travel'

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Have you ever tried to remember what you had for lunch yesterday? Who were you with? Where were you? Can you visualize the scene in your mind? The ability to recall past events, especially small details, is known as episodic memory. Recent research suggests that humans may share this ability with Eurasian jays, a type of bird.

With episodic memory, you recall specific events or episodes in your life, as explained by James Davies, the study's first author published in the journal PLOS One on May 15. When you remember, it feels like you're mentally reliving the moment. This type of memory also includes various details such as sounds, sights, your thoughts, and even your mood during that time.

Measured against a typical nectar feeder, the size of the Northern Giant Hummingbird is especially astonishing.

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Episodic memory is different from semantic memory, as explained by Davies, a psychology doctoral student at the Comparative Cognition Lab in the University of Cambridge.

Davies further elaborated, "Episodic memory is like remembering specific events, while semantic memory is more about knowing general facts. With semantic memory, there is no need for conscious recall."

Episodic memory is crucial for how we perceive the world around us. It can be challenging for scientists to determine if animals possess this ability since they cannot communicate their thoughts to us. Despite this, researchers have been conducting experiments for many years to explore animals' capacity to remember past events. Surprisingly, evidence of episodic-like memory has been discovered in a range of animals, including pigeons, dogs, and cuttlefish.

To find out whether Eurasian jays are capable of "mental time travel," researchers worked with birds trained to find food hidden under cups. Here, a Eurasian jay observes food being put in a cup with blue string.

Researchers conducted a study to determine if Eurasian jays have the ability of "mental time travel." They trained birds to locate food hidden under cups. During the study, a Eurasian jay watched as food was placed in a cup with blue string.

Corvids, such as crows, ravens, and jays, are known for their intelligence. Previous research has shown that they may have episodic-like memory, helping them remember where they have hidden food. In 1998, Dr. Nicola Clayton conducted an experiment with scrub jays to see if they could recall what types of food they had hidden and how long ago.

The method used to test episodic-like memory, known as the "what, when, where" protocol, has become a common approach for scientists studying animal memory. However, Davies, who is mentored by Clayton, aimed to explore alternative methods to assess this cognitive ability.

Using just one methodology may result in errors, according to Davies. It is better to use multiple methodologies that test the same thing in different ways to ensure more conclusive evidence.

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To improve the games, researchers turned to Eurasian jays for a new perspective. The results of their study could potentially impact the understanding of human memory.

Testing incidental memory

Davies and Clayton’s new experimental design drew upon the concept of incidental memory.

The concept behind human episodic memory is that we can recall specific details from past events, even if those details did not seem important at the time. According to Davies, we do not actively try to remember these details, but we may be able to recall them when asked about them later on.

This type of memory often involves remembering seemingly insignificant information, such as what you ate for lunch yesterday. This aspect of episodic memory is sometimes described as "mental time travel."

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The researchers wanted to see if Eurasian jays could mentally time travel, so they tested birds trained to find food hidden under cups. Davies lined up four red plastic cups and showed the birds where the food was placed. The jays then had to remember which cup contained the food. It was a simple task.

In the next part of the experiment, Davies made small changes to the cups, like adding stickers or colorful strings, but still hid the food under the same cup. To the birds, these changes were unimportant details - all they needed to focus on was the location of the cup to find the food.

A Eurasian jay chooses the same cup during the memory phase of the experiment.

A Eurasian jay chooses the same cup during the memory phase of the experiment.

James Davies

During the last part of the experiment, the small details of how the cups were decorated turned out to be surprisingly important. Davies decided to move the cups around so the birds couldn't use the previous clues to find the food. (The food had been taken out of the cups to make sure the birds weren't just following their noses.) Even after a short break, the jays were still successful in locating the cups with the treats.

Davies suggested that the birds might have been thinking about where the food was located based on their memories of the cup decorations. The jays were successful in using this information to find the hidden food.

Dr. Jonathon Crystal, a professor at the University of Indiana Bloomington, stated that this study provides strong evidence for episodic memory in Eurasian jays. Being able to recall information from earlier episodes is key in demonstrating episodic memory.

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Crystal highlighted the importance of studies like this one, which focus on animals' ability to form episodic memories, as they could contribute to human memory research.

Crystal explained that Alzheimer's disease is a major memory-related illness, with the most severe impact being a significant loss of episodic memory.

He emphasized the significance of testing Alzheimer's drugs on animals before human trials to ensure their effectiveness in targeting the specific type of memories affected in Alzheimer's patients.

Improving memory is important, but focusing on enhancing episodic memory is crucial, as mentioned by the expert. Developing better methods to test for episodic-like memory in animals can help achieve this goal.

Kate Golembiewski, a freelance science writer from Chicago, has a passion for zoology, thermodynamics, and the concept of death.

Editor's P/S:

The article delves into the intriguing realm of episodic memory, a cognitive ability that allows us to vividly recall specific events from our past, complete with rich details such as sights, sounds, and emotions. Recent research suggests that humans are not the only species capable of this remarkable feat, as Eurasian jays have also demonstrated evidence of episodic-like memory.

This discovery has significant implications for our understanding of animal cognition and could potentially contribute to advancements in human memory research. By studying the neural mechanisms underlying episodic memory in animals, scientists may gain valuable insights into the complexities of human memory and develop novel strategies for treating memory-related disorders such as Alzheimer's disease. Furthermore, the ability to accurately assess episodic-like memory in animals can pave the way for the development of more effective animal models for studying human memory and cognition.