Dogs are almost as forgetful as goldfish, according to a new study. They forget arbitrary events within two minutes.
Yeah, right. Then why do my two dogs rush into the kitchen when they hear food poured into their bowls? Why do dogs start freaking out the minute they realize they’re going to the vet?
According to “Animal Memory: A review of delayed matching-to-sample data,” published in a December issue of Behavioural Processes, dogs don’t remember specific events, but they do remember information that will help them survive, such as food locations.
Along with dogs, 24 other species — mammals, birds and bees — were included in the study. It was lead by Johan Lind, an ethologist at the Centre for the Study of Cultural Evolution at Stockholm University, Sweden.
The study tested the animals’ working memory, which it defined as “information about an event that is maintained for some time in the absence of reinforcement, and that can be used to guide behavior at a later time.” It focused on events with no biological significance, such as colored lights, visual patterns and sounds.
In layperson’s terms, “delayed matching-to-sample” (DMTS) refers to the process of showing an animal a sample stimulus (such as a colored light) for a few seconds, then removing it. After a timed delay, two comparison stimuli are shown to the animal. One matches the original stimulus while the other does not. The animal is rewarded with a food treat for choosing the one that matches the original stimulus.
“The data tell us that animals have no long-term memory of arbitrary events,” Lind told National Geographic. “We think humans’ ability to remember arbitrary events is unique.” This is known as episodic memory.
The study found that the average memory length was 27 seconds. Dogs’ memories were the longest, at 71 seconds, while bees’ were the shortest, at 2.4 seconds.
Surprisingly, chimpanzees had short memories — only 20 seconds. “It suggests human capacity for memory evolved after we branched from the most recent shared ancestor with chimps, over 6 million years ago,” according to National Geographic.
The results of studies like this will help scientists determine the memory abilities humans share with animals.
“The study of episodic memory is crucial, since it is still under debate whether other animals can retrieve memories of personal past events in the same way humans do,” Gema Martin-Ordas, of Newcastle University’s Institute of Neuroscience, told National Geographic.
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