‘Brain Trust’: Can Animals Remember When?

Two distinct groups of people spanning three generations seated themselves in the Irvine Barclay Theatre last Wednesday to hear the first presentation in the annual ‘Brain Trust’ series of lectures. Professor Nicola Clayton of Cambridge University, guest lecturer of the event, greeted them with a poster of the film ‘Back to the Future,’ with the question ‘Why is mental time travel such an important part of our daily lives?’ posted below it.
‘[Time travel] is important,’ stated Clayton, ‘because we do this every day. It’s what we do for a living, not just backwards, but to the future.’ Clayton then compared the physical time travel in the De Lorean vehicle, from the popular Michael J. Fox film trilogy, to mental time travel, such as reviewing past events or imagining events in the possible future.
The main question posed by Clayton was simple: ‘Can animals consciously remember?’ A recent study has shown that, although other animals can learn and benefit from experience, adjust, adapt, solve problems and make decisions, they cannot travel back into the past in their own minds. According to Clayton, this is a uniquely human trait, because we are consciously aware of ‘the fluidity of the passage of time,’ and are able to place a timestamp on every memory and sort them chronologically. This ability to associate an experience with times, places and emotions is called episodic memory.
Clayton proposed that, under a case study she supervised, evidence has been found in bird testing that suggests certain birds may also have the ability to create and learn from episodic memory.
In her experiment, Clayton used the Western Scrub-jay, a bird common to North America with a relatively large brain. Clayton began with a series of tests administered to children between 14 and 25 months old to determine the age at which a person is able to recall information stored as memory and make a choice based on that information. At around age five, children are able to consistently remember events and rely on episodic memories.
Clayton and her team of assistants then observed the Western Scrub-jay’s habits of storing food in different caches.
The jays provided no evidence of forgetting where their reserves were for over 256 days and hid perishable food, in addition to non-perishable nuts and acorns. The jays looked for the perishable worms after four hours, and non-perishable nuts after 124 hours, or five days, in their respective caches. When Clayton altered the environment by giving the jays food every two days, instead of several hours apart, the birds learned to store non-perishable nuts rather than the worms. ‘They increased their share of nuts to compensate,’ said Clayton, ‘It shows that their behavior is flexible and not robotic.’
In another test, Clayton and her team placed the jays into one of two rooms every morning, which the jays associated with either having breakfast or not, respective to each room. On the evening of the sixth day, stocked food was placed in an adjoining room. Remarkably, the jays took the food and saved it in the room with no breakfast. ‘What we’re arguing is that animals can plan,’ Clayton insisted. When compared to the tests administered to the children, Clayton asked, ‘Does this ability to plan emerge at the same time in children as the ability to remember the past?’ She plans to answer this question with further research.
The audience at the event consisted of high school students attending for extra credit, while the other half were middle-aged and older members of the community, mostly seasoned veterans of the Barclay Theater. Bill and Carole Thomas, two attendees of the event, have been coming to the ‘Brain Trust’ lecture series for several years. They stated that they always looked forward to the lectures, citing they were ‘consistently very excellent,’ and that this lecture in particular was ‘one of the better ones.’ Bill is a retired social studies teacher from Brea High School who frequents the Barclay Theater’s diverse intellectual and social events. ‘We think of moving away, but one of the major reasons for staying is the Barclay Theater,’ said Thomas.
The other half of the ticket holders were high school students from Corona del Mar, Fountain Valley, Newport Harbor and Aliso Niguel. Michael Suyama, Justin Grant and Maureen Darcy from Aliso Niguel came to the lecture for extra credit in their Advanced Placement Psychology class. The three students agreed that the event was very interesting and that it pertained to the class.
Clayton received her undergraduate degree in zoology at the University of Oxford and her doctorate in animal behavior at St. Andrews University. She became a professor at the University of California, Davis in 1995 and in 2005 moved back to Cambridge. Her next project will examine whether newborn chicks perform as well as older birds in specific tasks associated with memory development.