Neuroscientists at the University of Texas have released a groundbreaking study in the scientific journal Neuron revealing that mice may be able to recognize themselves in mirrors.
This study reveals new aspects of animal cognitive abilities and the brain's role in self-recognition.
The experiment used a group of black mice, each with a distinct white mark painted on their forehead, who were exposed to their reflection in a mirror.
The researchers found that mice already used to mirrors and raised among similar-looking cage-mates spent more time in front of the mirror, attempting to scrape off the white paint. This behavior, indicative of self-recognition, was linked to a specific set of neurons in the hippocampus — an area crucial for forming and retaining visual self-perception.
Further investigation revealed that vital neurons in the lower part of the hippocampus became active during the self-recognition process. When these neurons were intentionally removed, the mice no longer recognized that the white mark was out of place.
Additionally, gene expression analysis showed that mice raised in social isolation lacked the neuronal activity in the hippocampus associated with self-recognition. This finding underscores the importance of social experiences in developing neural pathways related to self-knowledge.
Neuroscientist Takashi Kitamura, the study's lead author, stressed the importance of the research to understanding how the brain processes self-identity, a relatively unexplored area compared to the recognition of others.
The researchers noted that while mice can detect changes in their appearance and pass the mirror test, this does not conclusively prove self-awareness. Unlike humans and chimpanzees, who do not require strong stimuli for self-recognition, mice need substantial sensory cues such as a visible mark to notice changes.