CRCNS: Collaborative Research: Characterizing Bayesian Surprise in Humans and Monkeys

惊讶的概念是感官处理、适应和学习、注意力和决策的核心。 然而，目前还没有广泛接受的数学理论来定量描述刺激或事件引起的惊喜，从单个神经元到复杂的自然或工程系统的观察者。 这个项目开发了一个正式的贝叶斯定义的惊喜，这是唯一的一致性制定下最小的公理假设。 Surprise通过测量观察者的后验信念和先验信念之间的差异，量化了数据如何影响自然或人工观察者。 初步的人眼跟踪实验表明，参与者在观看包括电视和视频游戏在内的复杂视频片段时，会注视令人惊讶的图像区域，这明显超出了预期。 这种行为背后的神经机制是什么？ 这个跨学科的建议解决了这个问题如下：-理论和建模，以研究惊喜如何与以前的显着性和新奇概念相关，并在分析神经功能和行为时可以有利地补充香农信息。猴子电生理学与简单的令人惊讶的刺激，以调查如何单神经元沿着感觉运动处理流（初级视觉皮层，额眼场，上级丘）可能会调制的惊喜。平行人/猴的心理物理学/电生理学，研究在自然环境中，在包括电视节目在内的更复杂的刺激下，吸引人和猴注意的刺激是否会携带更多的贝叶斯惊讶，这里发展的惊讶理论适用于不同的模态、数据库、任务和抽象层次。它有可能影响科学和工程，特别是计算机科学，数学，信息论，统计学，心理学和生物学教育。该研究涉及理论实验室（Baldi），建模和心理物理学实验室（Itti）和猴子电生理学实验室（Munoz）之间的合作的本科生，研究生和博士后学员。

The concept of surprise is central to sensory processing, adaptation and learning, attention, and decision making. Yet, no widely-accepted mathematical theory currently exists to quantitatively characterize surprise elicited by a stimulus or event, for observers that range from single neurons to complex natural or engineered systems. This project develops a formal Bayesian definition of surprise that is the only consistent formulation under minimal axiomatic assumptions. Surprise quantifies how data affects natural or artificial observers, by measuring the difference between posterior and prior beliefs of the observers. Preliminary human eye-tracking experiments demonstrated that participants gaze towards surprising image regions, significantly more than expected by chance, while watching complex videoclips including TV and video games. What are the underlyingneural mechanisms responsible for this behavior? This cross-disciplinary proposal addresses this question as follows:- Theory and modeling, to investigate how surprise relates to previous notions of saliency and novelty, and may advantageously complement Shannon information when analyzing neural function and behavior.- Monkey electrophysiology with simple surprising stimuli, to investigate how single-neurons along the sensorimotor processing stream (primary visual cortex, frontal eye fields, superior colliculus) may be modulated by surprise.- Parallel human/monkey psychophysics/electrophysiology, to investigate, in natural situations and with more complex stimuli including TV programs, whether stimuli which attract human and monkey attention may carry more Bayesian surprise.The theory of surprise developed here is applicable across different modalities, datatypes, tasks, and abstraction levels. It has potential for impacting science and engineering, and especially education in computer science, mathematics, information theory, statistics, psychology and biology. The research involves undergraduate, graduate, and postdoctoral trainees in a collaboration between a theory lab (Baldi), a modeling and psychophysics lab (Itti), and a monkey electrophysiology lab (Munoz).