Behavioral contrast occurs when a change in reinforcement rate in one context causes behavior to change in the opposite direction in another context. Positive contrast occurs when a decrease in the rate of reinforcement in one context results in an increase in behavior in another context. Negative contrast occurs when an increase in the rate of reinforcement in one context results in a decrease in behavior in another context. Research with nonhumans has found that positive contrast is more reliably produced than negative contrast. Research with nonhumans has also found that positive contrast is influenced to a larger degree by changes in reinforcement rate in the following context (vs. in the preceding context); however, results regarding negative contrast and the influence of preceding versus following contexts have been mixed. Finally, within-session contrast effects have been demonstrated in nonhumans. Relative to the entire environmental context, the largest change in behavior occurs immediately prior to (anticipatory contrast) or immediately following (local contrast) the change in reinforcement rate. Behavioral contrast has applied implications, in that practitioners may only be able to implement interventions in one context, which may result in concomitant worsening of behavior in other contexts. Few studies with humans have compared positive and negative contrast, and none have separated preceding- and following schedule effects or have systematically investigated within-session contrast. The purpose of this study was to investigate these effects in humans in a translational arrangement. Positive contrast was found in five of six cases, while negative contrast was found in only three of six. The effect of the following schedule was larger with positive contrast, but the effect of the preceding schedule was larger with negative contrast. There were no systematic within-session effects characteristic of anticipatory or local effects.

Escape from instructional demands is one of the most common functions of problem behavior. Some research suggests that a switch from difficult to easy tasks may function as a reinforcer for problem behavior. This is of particular concern for situations in which easy tasks are part of the intervention procedure to reduce problem behavior. This project examined the reinforcing effects of a switch from low-probability (low-p) to high-probability (high-p) tasks for individuals whose problem behavior was maintained by escape from demands. It also provided preliminary evidence as to the quality of reinforcement provided by a switch from low- high-p tasks. Three individuals with disabilities who were referred for treatment of escape-maintained problem behavior participated in this research. We used a multi-element design to compare the effects of two intervention conditions on problem behavior and compliance in relation to control and baseline conditions. During the control condition, no demands were presented, and the participant had continuous access to preferred items and attention. In the baseline condition (break), a break from low-p demands was presented contingent on problem behavior. In the first intervention condition, problem behavior no longer resulted in a break from demands (escape extinction). During the second intervention condition, problem behavior following low-p tasks resulted in a switch to high-p tasks. All participants engaged in elevated levels of problem behavior and decreased compliance when problem behavior resulted in a switch of tasks. These results imply that for individuals whose problem behavior is maintained by escape from demands, a switch from low- to high-p tasks may reinforce problem behavior.

Indiana University-Purdue University Indianapolis (IUPUI) / In accord with the cognitive model of poor functioning in schizophrenia, defeatist performance beliefs, or overgeneralized negative beliefs about one’s ability to perform tasks, have been linked to poor functional outcomes, cognitive impairment, and negative symptoms in schizophrenia and are a suggested therapeutic target in Cognitive Therapy for Schizophrenia. However, there is a paucity of research investigating these beliefs in schizotypy, or those exhibiting traits reflecting a putative genetic liability for schizophrenia. This study had three aims: to examine whether defeatist performance beliefs 1) are elevated in schizotypy compared to non-schizotypy, 2) are associated with functioning-related outcomes (i.e., quality of life, working memory, negative schizotypy traits), and 3) mediate the relationships between working memory and both negative schizotypy traits and quality of life. Schizotypy (n = 43) and non-schizotypy (n = 45) groups completed measures of schizotypy traits, defeatist performance beliefs, quality of life, and working memory. Results revealed that the schizotypy group reported significantly more defeatist performance beliefs than the non-schizotypy group. Within the schizotypy group, defeatist performance beliefs were significantly positively associated with negative schizotypy traits and significantly inversely associated with quality of life. No associations were observed between defeatist performance beliefs and positive schizotypy traits and working memory. Further, defeatist performance beliefs did not mediate the relationships between working memory and either quality of life or negative schizotypy traits. Findings are generally consistent with the cognitive model of poor functioning in schizophrenia and suggest that defeatist performance beliefs may be an important therapeutic target in early intervention services.

Indiana University-Purdue University Indianapolis (IUPUI) / Marijuana use is associated with many health risks, but is increasingly becoming more accepted; thus, use rates, as well as negative consequences, are growing. There is a need to better understand marijuana use behaviors so as to reduce its negative effects. The current study sought to test the viability of applying urgency theory to marijuana use behaviors by examining several pathways among negative urgency, marijuana-related attentional bias, coping motives, and marijuana use behaviors, across men and women. Participants (n=120, mean age= 26.61 years (SD=9.28), 50% women, 63% White/Caucasian) were recruited from the Indianapolis, IN area to participate in a cross-sectional study in which they completed self-report measures and a visual-probe computer task with eye-tracking following negative mood induction. Regression analyses and the PROCESS macro were used to examine study hypotheses. Several pathways were supported: Negative urgency was significantly associated with coping motives (β=0.24, p=0.01), coping motives were significantly associated with marijuana use behaviors (ΔR2= 0.55, p<0.01), and a serial mediation model was supported, in which the relationship between negative urgency and negative marijuana consequences was mediated by coping motives and then by marijuana use frequency (c’= 0.20, 95%CI= 0.06 to 0.50). Competing models were examined and not supported. There were no statistically significant pathways involving the attentional bias measures; although there was a pattern of small effect sizes demonstrating that attentional biases may relate to marijuana use behaviors in men and not in women. Findings from the current study serve as preliminary support for applying urgency theory to marijuana use behaviors. Overall, these findings suggest that negative urgency is a distal risk factor that influences the development of other, more proximal, predictors of marijuana use and negative marijuana consequences. Future studies should examine the time order of these relationships longitudinally to replicate and provide more confidence in the causal order of the model supported in the present study.

This study describes the biochemical activity and antimicrobial susceptibility patterns (antibiograms) of 104 gram-negative bacteria, represented by six species of bacilli, isolated from ten macaws of the genus Ara. Bacterial samples were acquired from fecal matter of six different species of macaws, ages one to three years, housed in a variety of locations. Bacteria from these samples were cultured onto selective media for classification. Identification and biochemical characterization were accomplished with the API 20E system. Escherichia (E.) coli accounted for 78% (81/1 04) of the total number of isolates. Antimicrobial susceptibility testing was done using the Kirby-Bauer method. Biotype and antimicrobial susceptibility data gathered in this study correspond with data of studies done on pigeons and llamas. These data show specific E. coli biotypes as members of the microflora of macaws.

No description available.

No description available.

Negative symptoms emerge early in the course of psychosis and are one of the best indicators of clinical outcomes; thus, the accurate, identification of these symptoms is paramount to early intervention efforts. Negative symptoms are typically assessed via self-report questionnaire or interviewer rated semi-structured interviews. However, the degree of concordance between self and interviewer report has been demonstrated to be low, approximately 50%. Therefore, it is important to identify the degree of discordance within each negative symptom domain (anhedonia, alogia, blunted affect, asociality, and amotivation) as well as to identify potential contributors to this lack of concordance. The present study examined each of the five negative symptom domains in regard to self and interviewer rating concordance in a sample (N = 70) that consists of a full range of negative symptoms and psychotic-like experiences (PLEs). Results indicated that self and interviewer report of negative symptom domains were inconsistently correlated. Dimensionally, asociality and avolition were the most concordant domains and alogia and anhedonia were more discordant. Although self and interviewer report scores of blunted affect did not significantly differ, each score may be capturing separate aspects of this experience. Participant drug use frequency was found to significantly impact rater responding on blunted affect, participant emotional clarity significantly impacted rater responding on alogia, participant clinical high risk (CHR) status impacted rater responding on consummatory anhedonia, and participant anxiety impacted rater responding on anticipatory anhedonia. This study identifies factors that underlie negative symptom rating discordance, which may help improve treatment intervention for those experiencing this critical phase of the disorder, and improve our ability to accurately monitor these symptoms in individuals with psychosis spectrum disorders. / Psychology

The current study examined the relationships between Major Depressive Disorder, negative life events, perceived parenting style, perceived family environment and Disruptive Behavior Disorders, specifically Conduct Disorder, Oppositional Defiant Disorder, and Attention-Deficit/Hyperactivity Disorder, in adolescent participants, (N = 381). Results indicated that those factors, with the exception of authoritarian parenting, correlated positively with symptoms consistent with Disruptive Behavior Disorders. In addition, the overall effect of those factors predicted symptoms consistent with Disruptive Behavior Disorders more strongly than each risk factor in isolation. In conclusion, results indicated that negative life events and symptoms consistent with Major Depressive Disorder mediated the effects of perceived parenting and perceived family environment on symptoms consistent with Disruptive Behavior Disorders.

No description available.