Choice behavior combines discrimination between distinctive outcomes, preference for specific outcomes and relative valuation of comparable outcomes. Previous work has focused on one component (i.e., preference) disregarding other influential processes that might provide a more complete understanding. Animal models of choice have been explored primarily utilizing extensive training, limited freedom for multiple decisions and sparse behavioral measures constrained to a single phase of motivated action. The present study used a paradigm that combines different elements of previous methods with the goal to distinguish among components of choice and explore how well components match predictions based on risk-sensitive foraging strategies. In order to analyze discrimination and relative valuation, it was necessary to have an option that shifted and an option that remained constant. Shifting outcomes among weeks included a change in single-option outcome (0 to 1 to 2 pellets) or a change in mixed-option outcome (0 or 5 to 0 or 3 to 0 or 1 pellets). Constant outcomes among weeks were also mixedoption (0 or 3 pellets) or single-option (1 pellet). Shifting single-option outcomes among weeks led to better discrimination, more robust preference and significant incentive contrast effects for the alternative outcome. Shifting multi-options altered choice components and led to dissociations among discrimination, preference, and reduced contrast effects. During extinction, all components were impacted with the greatest deficits during the shifting mixed-option outcome sessions. Results suggest choice behavior can be optimized for one component but suboptimal for others depending upon the complexity of alterations in outcome value between options.

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Concussions have recently become an area of concern among the general public, but a clear understanding of their total consequence is still being developed. Symptoms of concussions are wide-ranging, encapsulating a plethora of cognitive and emotional abilities that could be affected. Concussions transiently disrupt neural activation as well as behavioral responses across multiple categories. Skills pertaining to various aspects of emotions are often affected yet have rarely been studied after concussions. We present two case studies of collegiate athletes with a history of multiple concussions. This paper highlights the case of a collegiate athlete who had obtained two previous concussions with the most recent being sustained sixteen days prior to neuroimaging. A second athlete with two lifetime concussions was tested one year after the most recent injury. The current study utilized a novel emotional recognition task to assess the behavioral and neural effects of this injury. A group of five controls responded with high accuracy rates and quick response times to the task. They showed activation in regions of the frontal lobe as well as facial recognition areas of the occipital lobe. The 16-day case subject was impaired in recognizing emotions relative to controls and showed little to no overlap in brain activity for regions involved in emotional face processing. The athlete with a longer post-concussion period also showed residual effects of neural activity alteration when compared to controls with few overlapping active regions. Specific brain regions were activated in this group but not in controls including the sensorimotor cortex, supramarginal gyrus, and lateral occipital cortex. By taking a more individual approach in examination of neural activity post-concussion, we may be able to gain a better understanding of this heterogeneous injury.