Assessing potential reinforcement-like effects of brief stimuli unrelated to food reinforcers

It is widely assumed that reinforcers are biologically relevant stimuli, or stimuli that have been associated with biologically relevant stimuli. However, brief, arbitrary stimuli have also been reported to have reinforcement-like effects, despite being unrelated to biologically relevant stimuli like food. The present study explored the potential reinforcement-like effects of brief stimuli across 5 experiments. In Experiments 1 through 4, pigeon subjects responded for food reinforcement and brief stimulus presentations in a 2-component multiple schedule. Neither baseline response rates nor resistance to change during disruption tests were systematically greater in a component with versus without brief stimulus presentations. Increasing the rate and duration of brief stimulus presentations in Experiment 4 did not reveal reinforcement-like effects when compared directly with food. In Experiment 5, pigeons chose between independent terminal links in a concurrent-chains procedure. Across conditions, varying the location, duration, and rate of brief stimulus presentations in the terminal links had no systematic effects on preference. In contrast, varying rates of food reinforcers resulted in large and reliable shifts in preference. Therefore, the present study found no systematic evidence that brief stimuli unrelated to food reliably increase response rates, resistance to change, or preference. These data demonstrate the value of systematic replication, and a behavioral momentum approach to assessing potential reinforcement-like effects.     

Hope as a Predictor of Interpersonal Suicide Risk

The current study hypothesized that (1) hope would negatively predict burdensomeness, thwarted belongingness, and acquired capability to enact lethal injury; (2) hope would negatively predict suicidal ideation; and (3) the interpersonal suicide risk factors would predict suicidal ideation. Results indicated that hope negatively predicted burdensomeness and thwarted belongingness, but positively predicted acquired capability to enact suicide. Contrary to our second hypothesis, hope did not predict suicidal ideation, but interpersonal risk factors for suicide predicted suicidal ideation. Results are discussed in terms of implications for hope theory and Joiner's (2005) interpersonal risk factors for suicide, and for clinical practice.     

Audience Design in Multiparty Conversation

How do speakers design what they say in order to communicate effectively with groups of addressees who vary in their background knowledge of the topic at hand? Prior findings indicate that when a speaker addresses a pair of listeners with discrepant knowledge, that speakers Aim Low, designing their utterances for the least knowledgeable of the two addressees. Here, we test the hypothesis that speakers will depart from an Aim Low approach in order to efficiently communicate with larger groups of interacting partners. Further, we ask whether the cognitive demands of tracking multiple conversational partners' perspectives places limitations on successful audience design. We find that speakers can successfully track information about what up to four of their partners do and do not know in conversation. When addressing groups of 3–4 addressees at once, speakers design language based on the combined knowledge of the group. These findings point to an audience design process that simultaneously represents the perspectives of multiple other individuals and combines these representations in order to design utterances that strike a balance between the different needs of the individuals within the group.     

The assessment of child abuse potential and the prevention of child abuse and neglect: A policy analysis

A frequently advocated strategy for increasing the efficiency of child abuse prevention programs is to deliver prevention services to "high-risk" populations. This article critically reviews procedures for the reliable and valid assessment of child abuse potential within an ecological perspective. Factors that limit the usefulness of child abuse risk assessment are discussed. These factors include the uncertain criteria of child abuse and neglect, the low base rate of the phenomenon, and the financial and social costs of such procedures. Finally, the prevention implications of the current and future state of the art in child abuse risk assessment are considered and preventive interventions that do not depend on individual case risk screening are advocated.