July 19, 2013
Primates Can Remember Past Events
[ Watch the Video: Chimpanzees Have Long Term Memory ]
Alan McStravick for redOrbit.com - Your Universe Online
Each of us has experienced a situation where one of our senses has triggered a far off memory, transporting us instantly to the time when that memory was created. Whether it's a song that reminds you when you rolled 1,000 miles in your first vehicle or an aroma that takes you back to a beach holiday, our memory is what sets us apart from most other living creatures on earth by making it so we are not stuck in time.
The idea of "sense memory" applies to two unique concepts. The first, as noted above, links our five senses to specific points in time. The second, usually utilized by actors, involves actively seeking out the memory of how they once felt to tie themselves to the character they are trying to portray.
While each sense can be utilized for memory recall, the sense of smell is the most adept at drawing memories from the recesses of our minds. This has to do with the placement of the olfactory bulb immediately next to the part of the brain tasked with memory storage. In fact, a relatively new form of marketing is utilizing aromas to help evoke warm memories in the hopes it might encourage you to buy a certain product.
This highly specialized function of our brain has long been thought to be specific to humans. However, with new research published in the journal Current Biology, we are learning that our evolutionary cousins, the chimpanzee and orangutan, possess similar long-term memory recall that can be triggered by stimuli.
Researchers were able to show how, in laboratory tests, both primate species had very little problem with recollecting a specific tool-finding task they had been presented with only four times three years earlier. Additionally, the team was able to show the same recall from a singular event the primates experienced two weeks previously.
According to the researchers, apparently we have more in common with our primate cousins than was once believed. In this instance, the similarity is specific when it comes to autobiographical memories.
"Our data and other emerging evidence keep challenging the idea of non-human animals being stuck in time," says Gema Martin-Ordas of Aarhus University in Denmark. "We show not only that chimpanzees and orangutans remember events that happened two weeks or three years ago, but also that they can remember them even when they are not expecting to have to recall those events at a later time."
The animals involved in the study were able to distinguish between similar past events in which the identical tasks, locations and people were involved, Martin-Ordas added. "This is a crucial finding since it implies that our subjects were able to bind the different elements of very similar events - including task, tool, experimenter. [sic] This idea of 'binding' has been considered a crucial component of autobiographical memories."
The main experiment involved returning the chimpanzees and orangutans to a particular setup experienced in the past. In each of these situations, the animals were able to instantaneously remember where to search for tools and locate the tool they had only seen once. As noted in the video above, the team was particularly impressed with the complexity and speed of the primates' recall ability.
"I was surprised to find out not only that they remembered the event that took place three years ago, but also that they did it so fast!" Martin-Ordas says. "On average it took them five seconds to go and find the tools. Again this is very telling because it shows that they were not just walking around the rooms and suddenly saw the boxes and searched for the tools inside them. More probably, it was the recalled event that enabled them to find the tools directly."
According to the team, these new findings regarding our primate cousins present just the beginning of a novel approach to research on the science of memory for past events in non-human animals.
The performance of a task from memory is one thing. Perhaps as neuroscience progresses we might one day be able to determine if the smell of coconut tanning lotion also takes a chimp back to the sunny beaches of Cancun.