Can rats count? Neuroscientists have revealed the existence of number sense in rats
Using this research we can understand animal cognition better and also explore the neural basis of numerical abilities and disabilities in humans.
The collaborative research led by Professor Yung Wing-ho from the City University of Hong Kong (CityUHK) and Professor Ke Ya from The Chinese University of Hong Kong (CUHK) Faculty of Medicine was published in the journal Science Advances.
The researchers used methodologies combining numerical tasks, brain manipulation techniques and artificial intelligence modelling to find out whether rats can sense numbers. But why is this important?
What is number sense?
Number sense is defined as the ability to compare and manipulate nonsymbolic numerical quantities, plays a vital role in animals’ perception of the world and is closely linked to survival.
It is also the foundation of mathematical skills, a key component of human intelligence. However, it has never been determined if rats possess this cognitive ability.
Testing rats’ counting ability
The research team came up with a numerical learning task that minimised the influence of continuous magnitudes, allowing the rats to focus solely on numerical quantities.
By training rats to associate sounds with specific numbers, the study showed that rats can determine and categorise different numerical values, even without previous knowledge of numbers.
“Our study helps dissect the relationship between magnitude and numerosity processing. We discovered that when we blocked a specific part of the rats’ brain, called the posterior parietal cortex, their ability to understand numbers was affected but not their sense of magnitude,” explained Professor Yung.
When a specific brain region, the posterior parietal cortex, was blocked, the rats’ numerical comprehension was impaired, showing the existence of a dedicated brain area for number processing.
Helping us understand the human brain
Professor Ke from CU Medicine highlighted the broader implications of the findings. “The study not only solves a long-standing mystery about how brains handle numbers, but also offers new insights into studying the specific neural circuits involved in number processing in animals and how genes are associated with mathematical ability” she said.
Beyond scientific implications, the discovery could help address learning disabilities like dyscalculia, which affects people worldwide. By revealing the mechanisms of number sense in rats researchers hope to see a future with targeted interventions for people struggling with numerical difficulties.
