Magnitude and duration of the effects of cocaine on conditioned and adjunctive behaviors in the chimpanzee.

Characteristic patterns of conditioned key-pressing were maintained in the chimpanzee under a multiple 30-response fixed-ratio, 10-minute fixed-interval schedule of food presentation. Adjunctive drinking occurred with regularity during the fixed-interval schedule and, with less frequency, during 1-minute timeout periods that followed each food presentation; drinking seldom occurred during the fixed-ratio schedule. Cocaine increased key pressing under the fixed-interval schedule at doses between .1 and 3.0 mg/kg, but adjunctive drinking and key pressing under the fixed-ratio schedule did not increase at any dose. Conditioned and adjunctive behaviors were disrupted and suppressed for different durations at 10,0 mg/kg, a dose which induced convulsive seizures within 10 minutes after intramuscular injection. A time-course analysis showed the magnitude and duration of the effects of cocaine on key pressing under the fixed-interval schedule and on adjunctive drinking to be dose-related. Moreover, a given dose of cocaine had diverse effects, depending on the behavior and the time since drug administration.     

Effects of d-amphetamine on self-aggression and posturing in stumptail macaques

The behavioral effects of d-amphetamine sulfate were studied in adult male stumptail macaques living within a large heterogeneous group in an outdoor enclosure. Among five subjects that received a range of doses (.01 to .3 mg/kg), d-amphetamine increased self-aggressive behavior and abnormal posturing in subjects that exhibited these types of behavior prior to drug administration, but it had no effect in subjects not exhibiting those activities in the absence of the drug. For the former subjects, the dose-effect curves for self-aggression were of an inverted U-shape analogous to the effect of d-amphetamine on schedule-controlled behavior. Over the range of doses studied, the curve for abnormal posturing was monotonic. The data indicate that d-amphetamine can have effects on untrained behavior in individual animals in a quasinatural environment that are qualitatively and quantitatively similar to the behavioral effects observed in other laboratory environments, and that d-amphetamine does not evoke or increase a behavioral response in individual subjects that do not exhibit the response in the absence of the drug.     

The Meaning of Black Music

Donald Byrd is an internationally acclaimed jazz musician and has recorded over twenty albums. In this article he clearly states that Black music is an expression of the Black experience or the reality of Black life. Counseling, a process that engages the experience of the person(s) counseled, ignores an important expressive outlet Blacks have used in their struggle for survival. Dr. Byrd's article also outlines the dimensions of the Black aesthetic inherent in Black music. Black music is a manifestation of Black people, and if counselors are to understand Black people and facilitate their growth, they must listen to and understand the love, hurt, joy, despair, loneliness, pride, anger, and consciousness in Black music.     

Differences between students' estimated and attained grades in a first-year introductory psychology course as a function of identity development

Two hundred sixty-eight first-year university students were surveyed about the state of their identity development and their perceptions regarding chances for academic success in an introductory psychology course. In general, it was found that students who had an adult identity had a more accurate assessment of their chances for success in the course and also used more efficient study strategies. Students who had not completely formed an adult identity, however, were more inaccurate in estimates of their final grades and also seemed to use less productive study strategies. It was concluded that those who have formulated an adult identity might have also developed a more complete understanding of both themselves and their situation. Implications of the findings for further research regarding the effects of identity development on university life, as well as the implications for academic intervention programs, are discussed.     

Nonword repetition and phoneme elision in adults who do and do not stutter

The purpose of the present study was to explore the phonological working memory of adults who stutter through the use of a non-word repetition and a phoneme elision task. Participants were 14 adults who stutter (M=28 years) and 14 age/gender matched adults who do not stutter (M=28 years). For the non-word repetition task, the participants had to repeat a set of 12 non-words across four syllable lengths (2-, 3-, 4-, and 7-syllables) (N=48 total non-words). For the phoneme elision task, the participants repeated the same set of non-words at each syllable length, but with a designated target phoneme eliminated. Adults who stutter were significantly less accurate than adults who do not stutter in their initial attempts to produce the longest non-words (i.e., 7-syllable). Adults who stutter also required a significantly higher mean number of attempts to accurately produce 7-syllable non-words than adults who do not stutter. For the phoneme elision task, both groups demonstrated a significant reduction in accuracy as the non-words increased in length; however, there was no significant interaction between group and syllable length. Thus, although there appear to be advancements in the phonological working memory for adults who stutter relative to children who stutter, preliminary data from the present study suggest that the advancements may not be comparable to those demonstrated by adults who do not stutter. EDUCATIONAL OBJECTIVES: At the end of this activity the reader will be able to (a) summarize the nonword repetition data that have been published thus far with children and adults who stutter; (b) describe the subvocal rehearsal system, an aspect of the phonological working memory that is critical to nonword repetition accuracy; (c) employ an alternative means to explore the phonological working memory in adults who stutter, the phoneme elision task; and (d) discuss both phonological and motoric implications of deficits in the phonological working memory.     

Anxiety and Depression in Children and Adolescents: A Factor-Analytic Examination of the Tripartite Model

The tripartite model of Clark and Watson (1981) suggests that the oft-observed covariation between anxiety and depression can best be understood by examining three related yet distinct constructs: negative affectivity, positive affectivity, and elevated physiological arousal. In the present study, 510 boys and girls in the 4th, 7th, and 10th grades completed the Children's Depression Inventory and the Revised Children's Manifest Anxiety Scale. Confirmatory factor analyses were conducted to determine the goodness of fit of single-factor (i.e., negative affectivity), two-factor (i.e., anxiety and depression), and three-factor models (i.e., negative affectivity, positive affectivity, and physiological arousal). Analyses were conducted by examining each of the models in the whole sample first and then separately for boys and girls and for fourth, seventh, and tenth grade youths. Results failed to support the tripartite theory; rather, the findings supported a two-factor model in all cases. These factors represented the general constructs of anxiety and depression, and these factors remained significantly interrelated. Consistent with previous findings, the strength of these relations was stronger for boys than girls and for children than adolescents.     

One-month-old human infants learn about the social world while they sleep

Although infants display preferences for social stimuli early in their lives, we know relatively little about the mechanisms of infant learning about the social world. In the current set of studies, 1-month-old infants underwent an adapted eyeblink conditioning paradigm to examine learning to both 'social' and non-social cues. While infants were asleep, they were presented with either a 'social' stimulus (a female voice) or one of two non-social stimuli (tone or backward voice) followed by an airpuff presented to the eyelid. Infants in the experimental groups displayed increased learning across trials, regardless of stimulus type. However, infants conditioned to the 'social' stimulus showed increased learning compared to infants conditioned to either of the non-social stimuli. These results suggest a mechanism by which learning about the social world occurs early in life and the power of ecologically valid cues in facilitating that learning.     

Deconstructing the tower: Parameters and predictors of problem difficulty on the Tower of London task

The Tower of London (TOL) task has been widely used in both clinical and research realms. In the current study, 104 healthy participants attempted all possible moderate- to high-difficulty TOL problems in order to determine: (1) optimal measures of problem solving performance, (2) problem characteristics, other than the minimum moves necessary to solve the problem, that determine participants’ difficulty in solving problems successfully, quickly, and efficiently, and (3) effects of increased task experience on which problem characteristics determine problem difficulty. A factor analysis of six performance measures found that, regardless of task experience, problem difficulty could be captured well either by a single factor corresponding to general quality of solution or possibly by three subordinate factors corresponding to solution efficiency, solution speed, and initial planning speed. Regression analyses predicting these performance factors revealed that in addition to a problem’s minimum moves three problem parameters were critical in determining the problem difficulty: goal position hierarchy, start position hierarchy, and number of solution paths available. The relative contributions of each of the characteristics strongly depended on which performance factor defined performance. We conclude that TOL problem performance is multifaceted, and that classifying problem difficulty using only the minimum moves necessary to solve the problem is inadequate.     

State of Multicultural Neuropsychological Assessment in Children: Current Research Issues

Scientific attention to cultural considerations in child neuropsychological assessment has not developed parallel to the focus these issues have received in adult and elderly neuropsychological assessment. There are limited data on the presence, magnitude, etiology, and implications of culture-related differences in cognitive test performance among children. This preliminary report reviews the available empirical literature on the current state of multicultural neuropsychological assessment in children. The review identified articles by searching PubMed and PsycINFO databases, and the tables of contents of Developmental Neuropsychology and Child Neuropsychology from 2003-2008. Of the 1,834 abstracts reviewed, ten papers met inclusion criteria for the review. Five studies were completed in America; four of these compared performance between ethnic groups while the fifth examined neighborhood level poverty indicators exclusively within African-American children. Of the five international studies, all established local normative data and/or were exploratory investigations of neuropsychological functions in specific cultural groups, including Taiwanese infants, South African youth, and bilingual British children. Taken together, the results yield important clinical and research data that begin to inform many of the complex and fascinating mechanisms by which ethnic identity and culture impact cognitive development and the neuropsychological assessment of children. A critique of the existing literature and directions for future research are provided.