How bats track their targets in cluttered scenes revealed
A study has provided a new insight into how bats focus on their targets such as bugs through the trees in the dark of night.
It was found that 'temporal binding hypotheses' had the explanation. The hypothesis proposed that people and animals focus on objects versus the background when a set of neurons in the brain attuned to features of an object all respond in synchrony.
Amid a neuroscience debate about how people and animals focus on distinct objects within cluttered scenes, some of the newest and best evidence comes from the way bats "see" with their ears. Because bats have an especially acute need to track prey through crowded scenes, albeit with echolocation rather than vision, they have evolved to become an ideal testbed for the hypothesis.
It was established that as bat flies it emits two spectra of sound frequencies, one high and one low, into a wide cone of space ahead of it. Within the spectra are harmonic pairs of high and low frequencies, for example 33 kilohertz and 66 kilohertz. These harmonic pairs reflect off of objects and back to the bat's ears, triggering a response from neurons in its brain. Objects that reflect these harmonic pairs in perfect synchrony are the ones that stand out clearly for the bat.
Decades of research on how bats use echolocation to keep a focus on their targets not only lends support to a long debated neuroscience hypothesis about vision but also could lead to smarter sonar and radar technologies.
(Posted on 16-08-2014)