Working memory deficits, increased anxiety-like traits, and seizure susceptibility in BDNF overexpressing mice

BDNF regulates components of cognitive processes and has been implicated in psychiatric disorders. Here we report that genetic overexpression of the BDNF mature isoform (BDNF-tg) in female mice impaired working memory functions while sparing components of fear conditioning. BDNF-tg mice also displayed reduced breeding efficiency, higher anxiety-like scores, high self-grooming, impaired prepulse inhibition, and higher susceptibility to seizures when placed in a new empty cage, as compared with wild-type (WT) littermate controls. Control measures of general health, locomotor activity, motor coordination, depression-related behaviors, and sociability did not differ between genotypes. The present findings, indicating detrimental effects of life-long increased BDNF in mice, may inform human studies evaluating the role of BDNF functional genetic variations on cognitive abilities and vulnerability to psychiatric disorders.     

Affect regulation and temporal discounting: interactions between primed, state, and trait affect

Previous research has largely focused on the influence of experienced affect on decision making; however, other sources of affective information may also shape decisions. In two studies, we examine the interacting influences of affective information, state affect, and personality on temporal discounting rates (i.e., the tendency to choose small rewards today rather than larger rewards in the future). In Study 1, participants were primed with either positive or negative affect adjectives before making reward choices. In Study 2, participants underwent either a positive or negative affect induction before making reward choices. Results in both studies indicate that neuroticism interacts with state unpleasant affect and condition (i.e., positive or negative primes or induction) to predict discounting rates. Moreover, the nature of the interactions depends on the regulatory cues of the affective information available. These results suggest that irrelevant (i.e., primes) and stable (i.e., personality traits) sources of affective information also shape judgments and decision making. Thus, current affect levels are not the only source of affective information that guides individuals when making decisions.     

Change blindness and priming: When it does and does not occur

In a series of three experiments, we explored the nature of implicit representations in change blindness (CB). Using 3 x 3 letter arrays, we asked subjects (Ss) to locate changes in paired arrays separated by 80 ms ISIs, in which one, two or three letters of a row in the second array changed. In one testing version, a tone followed the second array, signaling a row for partial report (PR). In the other version, no PR was required. After Ss reported whether a change had been detected and the PR had been completed (if required), they were asked to identify a degraded letter trigram that was either novel, or from a previously shown row (repetition priming). Our findings indicate that when CB occurs, both the pre-change and post-change stimulus information primes despite its unavailability to consciousness. Surprisingly, findings also indicate that when change detection occurs only the post-change information primes.     

Different strategies for using motion-in-depth information in catching

Previous studies on ball catching have had the limitation that the catcher was restricted to lateral hand movements. The authors investigated catching behavior in the more natural situation in which hand movements were unconstrained. Movements of the hand were tracked as participants tried to "catch" an approaching ball simulated with changing size and/or changing disparity. Participants used 1 of 2 distinct interception strategies: (a) a "cutting-off" strategy where time to passage (TTP) information was used to guide movements of the hand in depth such that the ball was caught farther in front of the face when the ball was approaching more slowly and (b) a "waiting" strategy where the hand was moved along a frontoparallel plane that was constant across ball trajectories and speeds. Cue dissociation and selective adaptation manipulations demonstrated that the catcher's estimates of TTP and crossing distance were based on a combination of binocular and monocular information.     

Relationships among compulsive hoarding, trauma, and attention-deficit/hyperactivity disorder

The current study investigated aspects of post-traumatic stress disorder and attention deficit/ hyperactivity disorder (ADHD) among hoarders. Compared to a sample of 36 controls, hoarders (n=26) reported a significantly greater number of different types of trauma, more frequent traumatic experiences, more symptoms of inattention, hyperactivity, and greater comfort derived from possessions. These findings are consistent with previous reports of extensive comorbidity associated with hoarding behaviors, and may reflect the potential usefulness of assessing PTSD and ADHD symptoms at the outset of hoarding treatments, as well as considering alternative pharmacological interventions.     

Exploring the limits and utility of operant conditioning in the treatment of drug addiction

This article describes a research program to develop an operant treatment for cocaine addiction in low-income, treatment-resistant methadone patients. The treatment's central feature is an abstinence reinforcement contingency in which patients earn monetary reinforcement for providing cocaine-free urine samples. Success and failure of this contingency appear to be an orderly function of familiar parameters of operant conditioning. Increasing reinforcement magnitude and duration can increase effectiveness, and sustaining the contingency can prevent relapse. Initial development of a potentially practical application of this technology suggests that it may be possible to integrate abstinence reinforcement into employment settings using salary for work to reinforce drug abstinence. This research illustrates the potential utility and current limitations of an operant approach to the treatment of drug addiction. Similar research programs are needed to explore the limits of the operant approach and to develop practical applications that can be used widely in society for the treatment of drug addiction.     

A self-report typology of behavioral adjustment for young children

A large, national U.S. sample of children rated their own behavior and emotions using the Self-Report of Personality-Child version (SRP-C) of the Behavior Assessment System for Children (C. R. Reynolds & R. W. Kamphaus, 1992). Cluster analysis was used to group 4,981 self-reports (SRP-C) of children between the ages of 8 and 11 years. Theoretical and empirical considerations were used to identify a 10-cluster solution. Internal validation procedures revealed that the 10-cluster solution was well replicated by independently classifying 2 large subsamples of participants. External validation evidence revealed that only 2 of the 10 clusters could be differentiated by parent and teacher ratings of behavior problems. Peer ratings of social status and behavior, however, proved far better than adult ratings at differentiating the clusters. These findings suggest that the realm of intraindividual adjustment is not well understood by parents and teachers of these same children.     

Diurnal Patterns of Unpleasant Mood: Associations with Neuroticism, Depression, and Anxiety

The literature on symptoms of depression has included diurnal changes in mood. The morning-worse pattern is commonly mentioned. This pattern is often associated with endogenous or vegetative symptoms (e.g., weight and appetite loss, loss of pleasure, psychomotor retardation). However, depression researchers have also identified an evening-worse pattern of mood. This pattern is sometimes thought to be associated with milder depressive symptoms, and may characterize chronic dysthymia rather than clinical depression. The present study examines a nonclinical sample to test the hypothesis that an evening-worse diurnal pattern of mood would be associated with trait neuroticism, anxiety, and subclinical depressive symptoms. An experience sampling methodology was employed to assess mood three times a day for 60 consecutive days. This allowed us to calculate a reliable aggregate score for diurnal mood patterns. The evening-worse pattern was associated with many neurotic features, with scores on depression and anxiety measures, and with a cognitive style indicative of hopelessness. Discussion focuses on how an evening-worse diurnal pattern of mood may be indicative of mild subclinical depression, chronic dysthymia, or personality traits associated with negative affectivity.     

Social Anxiety in Children with Anxiety Disorders: Relation with Social and Emotional Functioning

Investigated the psychometric properties of the Social Anxiety Scale for children-Revised (SASC-R) as well as relations between social anxiety and children's social and emotional functioning. Participants were a clinic sample of children, ages 6–11 with anxiety disorders (N = 154) who completed the SASC-R. For a subset of these children, parent ratings of social skills, and self-ratings of perceived competence and peer interactions were also obtained. Factor analysis of the SASC-R supported the original three-factor solution and internal consistencies were in the acceptable range. Among children with simple phobia, scores on the SASC-R differentiated those with and without a comorbid social-based anxiety disorder. Social anxiety was also associated with impairments in social and emotional functioning. Specifically, highly socially anxious children reported low levels of social acceptance and global self-esteem and more negative peer interactions. Girls with high levels of social anxiety were also rated by parents as having poor social skills, particularly in the areas of assertive and responsible social behavior.