Biology is destiny only if we ignore it

Problems of sustainability and survivability are best met not with moralizing but with policies that take advantage of our increasingly understood evolved human psychology. This knowledge helps us understand why our problems recur, and why we need not expect them to have permanent solutions. What is needed is an evolutionary praxis. It is possible, for example, to create policies that work around our tendencies to hierarchize and to form into ethnocentric and mutually hostile groups. Although in many ways there may be a mismatch between our evolved human nature and contemporary society, the fact that it is we who construct our environments must reduce the extent of mismatch.     

Rats’ visual-spatial working memory: New object choice accuracy as a function of number of objects in the study array

When rats had to find new (jackpot) objects for rewards from among previously sampled baited objects, increasing the number of objects in the sample (study) segment of a trial from 3 to 5 and then to 7 (Experiment 1) or from 3 to 6 and 9 (Experiments 2 and 3) or from 6 to 9 and 12 (Experiment 4) did not reduce rats’ test segment performance. Increasing study segment size improved test segment performance contrary the limited-capacity hypothesis concerning rats’ spatial working memory. This effect occurred when objects either differed visually (Experiments 1, 2, 4) or only by odor (Experiment 3). Rats performed no better than chance in finding a jackpot on their first choice from among three visually different objects in Experiments 1 and 2. Furthermore, results from Experiments 2 and 3 indicate that differences in the probability of finding a jackpot by chance in Experiment 1 were not responsible for failure to find the predicted inverse relationship. Results from Experiment 4 indicate that those from Experiments 2 and 3 were not solely due to size of test arrays. We discussed whether our findings could be attributed to innate foraging or perceptual isolation processes during testing or to perceptual encoding processes during exposure to study segment arrays.     

Sequential learning models for the Wisconsin card sort task: Assessing processes in substance dependent individuals

The Wisconsin card sort task (WCST) is a commonly used neuropsychological test of executive or frontal lobe functioning. Traditional behavioral measures from the task (e.g., perseverative errors) distinguish healthy controls from clinical populations, but such measures can be difficult to interpret. In an attempt to supplement traditional measures, we developed and tested a family of sequential learning models that allowed for estimation of processes at the individual subject level in the WCST. Testing the model with substance dependent individuals and healthy controls, the model parameters significantly predicted group membership, even when controlling for traditional behavioral measures from the task. Substance dependence was associated with (a) slower attention shifting following punished trials and (b) reduced decision consistency. Results suggest that model parameters may offer both incremental content validity and incremental predictive validity.     

Evaluation of a preventive intervention for a self-selected subpopulation of children

Evaluated an experimental preventive intervention developed for children who perceived their parents as problem drinkers. The 8-session program was designed to improve children's coping, self-esteem, and social competence, and modify alcohol expectancies which were specified as mediators of the effects of parental alcohol abuse on child mental health. Participants were 271 self-selected 4th-, 5th-, and 6th-grade students in 13 schools. The children were randomly assigned to treatment or delayed treatment conditions and the program was given to three successive cohorts of students. A meta-analysis across three different cohorts indicated significant program effects to improve knowledge of the program content and the use of support- and emotion-focused coping behaviors for the full sample. A slightly stronger range of effects was found for a high-risk subsample. This research was funded by the National Institute of Mental Health Grant P50-MH39246 to support a Preventive Intervention Research Center and Prevention Training Grant T32-MH18387-02.