New Research From Psychological Science

Read about the latest research published in Psychological Science:

The Effect of Relative Encoding on Memory-Based Judgments

Marissa A. Sharif and Daniel M. Oppenheimer

Some theories of decision making suggest that when people encode a stimulus, they represent where the stimulus lies in a distribution rather than the absolute value of the stimulus. How does this tendency to represent information as relative rather than absolute influence decision making? In several studies, participants — at two timepoints — evaluated sound clips, the speed of toy cars, or the number of butterflies landing on flowers. When participants made memory-based judgments, they did so based on the distribution of options at the first timepoint (the time of encoding) rather than relying on the absolute value of the stimuli. They also failed to update their ranking of stimuli over time. This indicates that when people make decisions, they should be aware of the original context in which the stimuli were encoded because it can bias later judgments.

Treating Generational Stress: Effect of Paternal Stress on Development of Memory and Extinction in Offspring Is Reversed by Probiotic Treatment

Bridget L. Callaghan, Caitlin S. M. Cowan, and Rick Richardson   

Although some studies have indicated that treatment with probiotics positively influences stress-related physiology and affective functioning, no study has examined the impact of treatment with probiotics on the effects of stress experienced across generations. To examine this, the researchers studied two generations of rats (F0 and F1). Male F0 rats were reared in a stressful environment (maternal separation) or a standard environment. Some F0 rats were given probiotic treatment in infancy and some were not. F0 rats were then bred, becoming fathers to the F1 generation. Some F1 generation rats were given probiotics in infancy and others were not. All F1 rats completed an aversive conditioning paradigm and an extinction procedure. Researchers found longer-lasting aversive associations and increased extinction relapse in F1 rats whose fathers (F0) had experienced maternal separation. This effect was reversed in F1 rats that had been treated with a probiotic and in F1 rats whose fathers (F0) had been treated with probiotics, findings that may inform efforts to better identify and treat those at risk for intergenerational stress.