Effects of fornix transection upon associative memory in monkeys: Role of the hippocampus in learned action

Thirty-three monkeys took part in seven experiments designed to elucidate further the effect of fornix transection on learning and memory. In the first experiment the monkeys had to remember whether stimulus objects had previously been paired with reward or no reward, and they had to use this memory to guide choice between stimulus objects at retention tests according to an arbitrary rule which they had learned: to choose objects previously paired with no reward in preference to objects previously paired with reward. Fornix transection produced a severe and permanent impairment in this task. In the second experiment the monkeys also had to remember object-reward associations but the performance rule was more natural: to choose objects previously paired with reward. Here fornix transection had no effect. The third experiment required the monkeys to remember, given a stimulus object, which of two events of equal valence had previously been the outcome of displacing that object. The two events were either a peanut and a sultana or a black penny and a white penny of equal secondary reinforcing value. Performance was unimpaired by fornix transection. The fourth experiment also demonstrated, in a different paradigm, unimpaired recall of sensory events. The fifth experiment demonstrated an impairment following fornix transection in acquisition of simultaneous spatial-visual conditional discriminations; the sixth demonstrated normal learning by fornix-transected monkeys of a successive spatial-visual conditional discrimination and the seventh demonstrated unimpaired acquisition of a simultaneous auditory-visual conditional discrimination. These results, when considered in detail and together, are incompatible with existing hypotheses of hippocampal function. A new hypothesis is discussed.     

Physical activity and sedentary behavior: a population-based study of barriers, enjoyment, and preference.

The associations of physical activity and sedentary behavior with barriers, enjoyment, and preferences were examined in a population-based mail survey of 1,332 adults. Respondents reporting high enjoyment and preference for physical activity were more likely to report high levels of activity. Those reporting cost, the weather, and personal barriers to physical activity were less likely to be physically active. Preference for sedentary behavior was associated with the decreased likelihood of being physically active, and the weather a barrier to physical activity was associated with the increased likelihood of sedentary behavior. These constructs can be used to examine individual and environmental influences on physical activity and sedentary behavior in specific populations and could inform the development of targeted interventions.     

Alliance and Group Cohesion in Relationship Education

Relationship education programs have been shown as an effective way to increase relationship functioning. There is less known about how process factors, such as alliance with the leader or group dynamics, affect outcomes in these interventions. We examined group cohesion and alliance with the leader in a relationship education program tailored for individuals. Specifically, we examined whether participants' ratings (n = 126) of the group cohesion and alliance with the leader were associated with changes in relationship adjustment, relationship confidence, and communication quality from pre‐ to postintervention. The results demonstrated that participants' perceptions of the cohesion among the members in their relationship education group, but not the leader–participant alliance, made a significant contribution to the changes in participants' relationship functioning. These results suggest that the group dynamics among the members in the group are important ingredients in relationship education. Implications for relationship programs are provided.