Symbolic quantitative cognition in wild zebrafish

Symbolic quantitative cognition in wild zebrafish (Danio rerio). Nawaf Abdul Majeed, Dhairrya Singh, Akshita Baiju Gopal, Tanya Battiwala, Ninaad Kulshreshtha, Rahulraj Mishra, Shagun Sabharwal, Madhusmita Behera, Manisha Sahu, Ameya Menon, Lalchhanhimi Bungsut, Amiya Walia, Raksha Saraf, Susan Mathew, Ashumi Shah, Suhaavi Kochhar, Nivedita Salar, Sushmita Thakuri, Yashant Sharma, Nishtha Rampuria, Anubhab Bhattacharjee, Niharika Wagh, Sahana Hegde, Indira Bulhan, Gurasheesh Singh,  Bittu Kaveri Rajaraman. bioRxiv, Mar 19 2022. https://doi.org/10.1101/2022.03.17.484678

Abstract: Zebrafish (Danio rerio) constitute an excellent model system to investigate the neural and genetic basis of quantitative cognition because of the single neuron resolution of calcium imaging of awake, behaving fish. While nonsymbolic numerical cognition has been investigated across many taxa, symbolic numerical cognition has not been investigated among fish. We developed a novel quantitative symbolic test for zebrafish using an operant conditioning paradigm in which the number of horizontal lines zebrafish approached in a 2-alternative forced choice task predicted the number of food reward pellets they would receive. Zebrafish did not at the population level learn a preference for the 2-line stimulus predictive of receiving 2 food pellets. However, they performed significantly above chance in a nonsymbolic discrimination task with the same apparatus, in which the 2-line stimulus was associated with the same reward but the choice of the 1-line stimulus was not rewarded. We also explored the explanatory value of alternative spatial learning hypotheses such as a Win-Stay, Lose-Shift (WSLS) strategy at the individual level for fish in navigating these spatially randomised tasks. The implications of this for symbolic versus nonsymbolic quantitative cognition in this model system are discussed relative to reward type and stimulus modality.