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Relative Reward And Operant Behaivor, Howard Cromwell Apr 2015

Relative Reward And Operant Behaivor, Howard Cromwell

Howard Casey Cromwell

No abstract provided.


Polychlorinated Biphenyl Exposure Alters Oxytocin Receptor Gene Expression And Maternal Behavior In Rat, Howard Cromwell Dec 2014

Polychlorinated Biphenyl Exposure Alters Oxytocin Receptor Gene Expression And Maternal Behavior In Rat, Howard Cromwell

Howard Casey Cromwell

Polychlorinated biphenyl (PCB) is a persistent organic pollutant known to induce diverse molecular and behavioral alterations. Effects of PCB exposure could be transmitted to future generations via changes in behavior and gene expression. Previous work has shown that PCB-exposure can alter social behavior. The present study extends this work by examining a possible molecular mechanism for these changes. Pregnant rats (Sprague-Dawley) were exposed through diet to a combination of non-coplanar (PCB 47 - 2,20,4,40-tetrachlorobiphenyl) and coplanar (PCB 77 - 3,30,4,40- tetrachlorobiphenyl) congeners. Maternal care behaviors were examined by evaluating the rate and quality of nest building on the last 4 …


Emotion And Relative Reward Processing: An Investigation On Instrumental Successive Negative Contrast And Ultrasonic Vocalizations In The Rat., Howard Cromwell Sep 2014

Emotion And Relative Reward Processing: An Investigation On Instrumental Successive Negative Contrast And Ultrasonic Vocalizations In The Rat., Howard Cromwell

Howard Casey Cromwell

Incentive contrast effects include changes in behavioral responses after a reward upshift (positive contrast) or downshift (negative contrast). Proposed influences on these behavioral changes are emotional state reactions after experiencing or anticipating a change in reward outcome. Rat ultrasonic vocalizations have been shown to be indicators of emotional state during behavior and anticipatory periods. The objective of the present study was to monitor rodent ultrasounds during incentive contrast using a classical runway procedure called instrumental successive negative contrast. The procedure is one that has been used often to examine incentive relativity because of its reliability in measuring negative contrast effects. …


Effects Of Polychlorinated Biphenyl (Pcb) On Response Perseveration And Ultrasonic Vocalization Emission In Rat During Development, Howard Cromwell Dec 2013

Effects Of Polychlorinated Biphenyl (Pcb) On Response Perseveration And Ultrasonic Vocalization Emission In Rat During Development, Howard Cromwell

Howard Casey Cromwell

The 3 major symptoms of autistic spectrum disorders include 1) social behavioral alterations, 2) problems in communication and 3) higher-order motoric deficits of perseveration and stereotyped movements. Previous work has shown that early developmental exposure to polychlorinated biphenyls (PCBs) alters rat pup social motivation and juvenile rat social recognition/investigation. The present work extends this previous research by examining how perinatal PCB exposure alters motoric functions and communication abilities at different stages of development. Action perseveration was examined using performance measures from a T-maze environment. Communication abilities were evaluated by monitoring ultrasound emission in rat pups during a brief isolation from …