Adam Smith
Into the minds of giants: accessing the sensory-perceptual neurobiology of whales in the wild
A central goal of neuroscience is to understand how the nervous system generates complex behavior, yet due to methodological and ethical tradeoffs, we have almost no knowledge of how animal brains rapidly receive, process, and respond to information in the dynamic environments in which they evolved. This project overcomes these tradeoffs by non-invasively measuring sensory-perceptual neural responses from free-swimming cetacean marine mammals in the wild.
I will develop a non-invasive multi-channel EEG biologging tag to record auditory brainstem responses (ABRs) and auditory cortical responses (ACRs) from cetaceans during natural behavior. Tags will be tested on trained harbor porpoises, then deployed on three wild species (harbor porpoises, humpback whales, and sperm whales) that span the cetacean brain-body size spectrum and major ecological and phylogenetic differences. Data will be synchronized with movement and acoustic recordings to link brain activity to acoustic stimuli in real time. Porpoises and sperm whales will provide abundant self-generated biosonar signals, while humpback whales will receive playback of controlled acoustic stimuli, enabling the first hearing measurements from baleen whales in natural conditions.
Large whales cannot be restrained, and therefore EEG-tags are remotely and precisely deployed on free-swimming whales using drones.This project will establish a new state-of-the-art in neuroethology and systems neuroscience, producing the first empirical hearing data from humpback and sperm whales, and the first sensory-perceptual neural measurements from any cetacean or non-human animal in nature. Full success will open the door to unprecedented comparative studies of sensory processing, cognition, and physiological adaptation in large-brained animals that cannot be ethically restrained.
