Visual object categorization in birds and primates: Integrating behavioral, neurobiological, and computational evidence within a “general process” framework

Abstract

Previous comparative work has suggested that the mechanisms of object categorization differ importantly for birds and primates. However, behavioral and neurobiological differences do not preclude the possibility that at least some of those mechanisms are shared across these evolutionarily distant groups. The present study integrates behavioral, neurobiological, and computational evidence concerning the "general processes" that are involved in object recognition in vertebrates. We start by reviewing work implicating error-driven learning in object categorization by birds and primates, and also consider neurobiological evidence suggesting that the basal ganglia might implement this process. We then turn to work with a computational model showing that principles of visual processing discovered in the primate brain can account for key behavioral findings in object recognition by pigeons, including cases in which pigeons' behavior differs from that of people. These results provide a proof of concept that the basic principles of visual shape processing are similar across distantly related vertebrate species, thereby offering important insights into the evolution of visual cognition.

Pattern recognition algorithm reveals how birds evolve individual egg pattern signatures

“…The extracted features correlate with parts of a visual scene to which primates are most likely to pay attention 31 . Although birds do not have structures homologous to those in the ventral stream of the primate visual cortex, the avian tectofugal pathway-which plays a dominant role in visual discrimination tasks-is believed to operate in a similar way, with recent work supporting the view that the general processes involved in object recognition are widely conserved in vertebrates 28 . In primates and birds, visual processing occurs in different regions of the brain, with different features extracted and represented at various stages of the visual pathway 28,32,33 .…”

“…However, many aspects of avian pattern recognition remain poorly understood 28 , so our model provides a roughly analogous representation rather than a complete description of the cognitive processes involved in avian pattern perception. Discovering which biologically inspired models of object recognition best approach the capabilities of real primate and avian visual systems is an important goal for the future 35 .…”

“…In later stages, neurons encode features with intermediate complexity, such as shapes or markings that are largely invariant to transformation and rescaling; SIFT extracts and analyses these features of intermediate complexity 26,29 . Intermediate features likely play a specific and important role in object classification in primates 33 , and recent evidence suggests that birds too make use of these features in object recognition tasks 28,34 .…”

“…Our study provides a first step towards understanding how hosts have evolved individual signatures that are easy to recognize but difficult to forge. As computational neuroscience models become more sophisticated 42 and as we learn more about real-world object recognition in birds 28 , future researchers will be well equipped to investigate not only egg signatures but also broad questions related to recognition (for example, of kin or mates) in other natural contexts.…”

“…To then quantify egg pattern signatures as the avian brain might process them, we introduce NATUREPATTERNMATCH, a computer vision programme based on object recognition algorithms that detect, describe and compare local features in a visual scene 26,27 . These 'signature' features are analogous to those used by primates and birds in real object recognition tasks 28,29 . For each host species, we then conduct a simulation in which each egg image must be matched to its correct clutch on the basis of its pattern alone, yielding a single measure of signature recognizability.…”