Beecause I forgot: Bumblebees get their memories mixed up too

Bumblebees have been shown to misremember traits of desirable stimuli, conflating two familiar traits to pursue an unfamiliar mix.

Have you ever been in the middle of recounting a personal anecdote and gotten half way through before realising that it didn’t actually happen to you? Maybe the story you’re telling was actually from a movie, or maybe it’s a friend’s story instead – either way, you just incorporated an impersonal memory into your own life story.

If that has happened to you, don’t worry, because people are prone to that sort of mistake. It’s in our embarrassing human natures, but only human natures. That is, until researchers observed the same type of memory misattribution in bumbling bees, I mean, bumblebees.

Researchers from the Queen Mary University of London may have been the first to detect false memories in non-human animals, the humble bumblebee (Bombus terrestris).

The animals were trained to associate a particular coloured ‘flower’ with nectar rewards: one group, yellow flowers; the other, black and white (b&w). Next, the animals were re-trained to preference the opposite colour for their sugary reward.

Shortly after, the bees were given the option to choose between both types of flower. Here, the bees flew to the colour where they were most recently rewarded, where the treat was most fresh in their tiny insect minds. Even when a third flower-type was introduced, a yellow-b&w hybrid, the bees still chose the type that gave the reward most recently. Both groups beehived similarly and as expected.

The bees were then re-tested 1 and 3 days later. Group A, which was most recently trained to seek out black and white flowers for reward, frequented the b&w stimulus over the 20 trials.

The other group, which was most familiar with seeking a purely yellow flower for reward, selected those yellow flowers for the first five trials. But then – the researchers speculate – the bees’ ‘yellowness’ search image conflated with their now dim ‘b&w ringed’ search image, curbing the bees to seek the yellow-ringed hybrid flower, the sugary alien pattern with characteristics of nectar past.

Further tests revealed that the second group of bees were indeed getting their past two flower experiences mixed up.

The researchers suggest that the capacity for sophisticated memory, such as that of humans and bees, brings with it the capacity for failures in that memory. Since we are able to identify patterns, ‘circles’ and ‘colours’ etc., and store them in our brains, we are left susceptible for our memory to dredge up those identifiable patterns in the wrong order and potentially even merge them together.

So next time, when you’re at a party telling people about ‘that time at band camp’ or ‘that time when you were foraging for nectar in the wrong flowers’ and realise you’re confabulating, don’t be embarrassed, because insects with tiny, tiny brains make the same mistakes too.

Originally published at Think Inc.

Paper – Kathryn L. Hunt, Lars Chittka. Merging of Long-Term Memories in an Insect.Current Biology, 2015; DOI: 10.1016/j.cub.2015.01.023

Feature image – Andrés Morya/Flickr/CC BY-NC 2.0