Stability of the Kaufman Assessment Battery for Children for a sample of Mexican-American children

Test-retest stability of the Kaufman Assessment Battery for Children (K-ABC) was investigated over a 5$\text{1}\text{2}$-month interval for 42 Mexican-American preschool/kindergarten children. The results indicated that the stability coefficients for K-ABC Global scales and subtests were generally of adequate magnitudes (e.g., .70s and .80s), providing some evidence that the K-ABC is a relatively stable instrument for the sample. The results are discussed in the context of a test-retest study reported in the K-ABC Manual. Global scale stability coefficients were found to range from .76 to .90, and for the subtests the coefficients ranged from .26 to .89. The patterns of gain scores were very similar to the patterns reported in the stability investigation in the K-ABC Manual.     

Determination of a behavioral transfer function: White-noise analysis of session-to-session response-ratio dynamics on concurrent VI VI schedules

Six pigeons were exposed to concurrent variable-interval schedules in which the programmed reinforcer ratios changed from session to session according to a pseudorandom binary sequence. This procedure corresponded to the stochastic identification paradigm (“white-noise experiment”) of systems theory and enabled the relation between log response ratios in the current session and log reinforcer ratios in all previous sessions to be determined. Such dynamic relations are called linear transfer functions. Both nonparametric and parametric representations of these, in the form of “impulse-response functions,” were determined for each bird. The session-to-session response ratios resulting from the session-to-session pseudorandom binary variations in reinforcer ratios were well predicted by the impulse-response functions identified for each pigeon. The impulse-response functions were well fitted by a second-order dynamic model involving only two parameters: a time constant and a gain. The mean time constant was 0.67 sessions, implying that the effects of abrupt changes in log reinforcer ratios should be 96% complete within about five sessions. The mean gain was 0.53, which was surprisingly low inasmuch as it should equal the sensitivity to reinforcement ratio observed under steady-state conditions. The same six pigeons were subjected to a similar experiment 10 months following the first. Despite individual differences in impulse-response functions between birds within each experiment, the impulse-response functions determined from the two experiments were essentially the same.     

Aggression in toddlers: Responses to the assertive acts of boys and girls

Sex Roles - Forty-eight toddler boys and girls, 18 to 36 months of age, were observed in play groups. The assertive acts of each child and the responses of peers and teachers were recorded. The...     

Appetitive differential conditioning of the rabbit’s jaw movement response

Two experiments examined appetitive differential conditioning of the rabbit’s jaw movement response (JMR) in a two-phase procedure. The first phase entailed reinforced training with one conditioned stimulus (CS+), and the second phase involved intermixed presentations of CS+ and an unreinforced stimulus (CS?). In Experiment 1, CS+ was a 600-Hz tone, and CS-was either a 660-,1,000-, or 2,100-Hz tone. In Experiment 2, the magnitude of the water unconditioned stimulus (US) paired with CS+ was either 1, 3, or 9 ml. The experiments revealed that 1) the level of responding to CS-rose for several days and then declined over the remainder of training; 2) the physical similarity between CS+ and CS?directly affected the level of responding to CS?but had no discernable effect on the level of responding to CS+ ; and 3) US magnitude positively affected the level of responding to CS + and, to a lesser extent, CS?. The results are discussed in terms of their implications for Spence’s gradient interaction theory and Pavlov’s external inhibition hypothesis.     

Unresolved grief

This paper has reviewed the literature on bereavement and, with particular emphasis on the authors' own work, describes three syndromes which seem to be related to the nonresolution of distinct phases of the grief process. The possibility of unresolved grief should receive a high index of suspicion for the patient with otherwise unexplainable depression, chronic illness behavior, or symptoms similar to those of a deceased relative or friend. When any of these syndromes are identified, it is useful to ask the patient who he has lost, how he has lost them, how he felt about the loss, whether he felt that he grieved, whether he still cries or feels the need to cry, and whether he has adjusted. The answer to these questions--both verbal and nonverbal--will help identify unresolved grief, when present, and may be a guide to specific interventions. On the other hand, our studies have suggested that unresolved grief is a somewhat overly simplistic concept. Most, if not all, people never totally resolve their grief; significant aspects of the bereavement process go on for years after the loss, even in otherwise normal patients. For some, identification syndromes continue. Others may continue to feel the presence of the deceased or have daily visions of him or her. Still others may feel pain, anger, and guilt for years after the death. It is still unclear at what point and to what degree these behaviors and symptoms become medical or psychiatric concerns and become pathological or predispose to serious medical, psychological, or social complications. Investigations into these unreported areas have been initiated and, we trust, will lead to clinically useful answers.     

Accommodation to increased accuracy demands by the right and left hands

This study was designed to identify the phase of rapid aimed movements responsible for hand differences in motor skill, and to evaluate potential differences between the hands in accommodating to greater accuracy demands. In both experiments, an accelerometer mounted on a stylus allowed key changes in acceleration to be used to partition the movement into phases. In Experiment 1, slower left hand movement times were attributable primarily to a terminal homing-in phase, especially as target size decreased. Since error rates varied as a function of hand and target size, speed-accuracy trade-offs may have occurred. Experiment 2 rigidly controlled error rate and confirmed the major hand difference to occur in the latter phase of the movement where error correction is presumed. Although less pronounced, adjustments were made in the earlier movement phases as well. Accommodation to greater accuracy demands involved moving the stylus closer to the target before decelerating to engage in error correction. This adjustment to gain enhanced precision was more pronounced in the left hand.     

Antidepressant treatment of children: clinical relapse is unrelated to tricyclic plasma concentrations

Plasma concentrations of imipramine and amitriptyline and their desmethylated metabolites were measured in 20 children being treated for major depressive illness 2 wk. and 5 to 10 wk. after achieving drug dosages of 2.25 mg/kg body weight. At 2 wk. all children had exhibited clinical improvement, but by 10 wk. 4 of the 10 children treated with imipramine and 5 of the 10 children treated with amitriptyline had experienced clinical relapse of depressive symptoms. Tricyclic antidepressant plasma concentrations and ratios were comparable in the subgroups of children who maintained their clinical improvement and those who relapsed. There was no evidence of a systematic decline in plasma tricyclic antidepressant concentrations in those children who relapsed.     

Infant hypotonia, obesity, hypogenitalism and oligophrenia--new viewpoints on the etiology and symptoms of Prader-Willi syndrome

We present four cases of Prader-Willi syndrome. Two of them have an abnormality of a chromosome 15, the other both show different chromosomal abnormalities. Translocations or deletions were found recently in the bands 15q11/12 in about 60% of the cases of Prader-Willi syndrome. The consequences for diagnosis, symptomatology and genetic counselling of the syndrome are discussed.