Integration of sensory and reward information during perceptual decision-making in lateral intraparietal cortex (LIP)
Abstract/Contents
- Abstract
- The work presented in this dissertation primarily focuses on decision-related activity in the lateral intraparietal area (LIP) and, secondarily, the dorsolateral prefrontal cortex (DLPFC). In Chapter 1 we review the previous independent investigations indicating that these areas are separately modulated by sensory information, value information and choice appropriate to represent decisions. We argue that when both sensory and value information must be simultaneously integrated to make choices, it is unknown, if, how and when these areas integrate these factors. We present a behavioral paradigm in which animal subjects must combine sensory and value information, on a trial-to-trial basis, to make optimal choices. This paradigm is based on a well-known motion discrimination task; however, in our task the magnitude of the reward associated with each option varies from trial to trial. On some trials both options are worth equally large or small rewards. On other trials one option's reward is greater than that of the other. In Chapter 2, we demonstrate that in the unequal reward conditions subjects' choices are consistently biased towards the greater magnitude option. Additionally, we will show that this bias is independent of the motion stimulus strength and its magnitude is nearly optimal. In Chapter 3, we observe that single neurons in cortical area LIP consistently, simultaneously and dynamically represent both sensory and value information. We will argue that this representation supports an integrator model of decision making, in which sensory information is accumulated until the decision is resolved by a threshold crossing. Our results support an interpretation of this model in which value information adjusts the likelihood of a threshold crossing by iv raising or lowering the accumulator's initial state. In Chapter 4, we present a preliminary comparison between LIP and DLPFC activity, under identical conditions, suggesting they play fundamentally different roles in decision making. In Chapter 5, we discuss future lines of research.
Description
| Type of resource | text |
|---|---|
| Form | electronic; electronic resource; remote |
| Extent | 1 online resource. |
| Publication date | 2011 |
| Issuance | monographic |
| Language | English |
Creators/Contributors
| Associated with | Rorie, Alan E |
|---|---|
| Associated with | Stanford University, Department of Neurobiology. |
| Primary advisor | Newsome, William T |
| Thesis advisor | Newsome, William T |
| Thesis advisor | Knutson, Brian |
| Thesis advisor | Moore, Tirin, 1969- |
| Thesis advisor | Shenoy, Krishna V. (Krishna Vaughn) |
| Advisor | Knutson, Brian |
| Advisor | Moore, Tirin, 1969- |
| Advisor | Shenoy, Krishna V. (Krishna Vaughn) |
Subjects
| Genre | Theses |
|---|
Bibliographic information
| Statement of responsibility | Alan Edward Rorie. |
|---|---|
| Note | Submitted to the Department of Neurobiology. |
| Thesis | Ph.D. Stanford University 2011 |
| Location | electronic resource |
Access conditions
- Copyright
- © 2011 by Alan E Rorie
- License
- This work is licensed under a Creative Commons Attribution Non Commercial No Derivatives 3.0 Unported license (CC BY-NC-ND).
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