An ACTH4-9 analog (ORG 2766) speeds recovery from septal hyperemotionality in the rat

The amount of hyperemotionality initially demonstrated after septal area lesions was reduced, and the rate at which the hyperemotionality attenuated over repeated testing, was enhanced by the administration of an ACTH4-9 analog, ORG 2766. This ACTH fragment was given for 4 consecutive days after surgery but terminated before testing began. Two weeks after the daily tests of emotionality, the animals were trained in a two-way active avoidance task. The typical increase in avoidance behavior seen in animals with septal lesions was observed in the lesioned animals tested with ORG 2766, but the usual high number of intertrial responses was greatly reduced in these animals. The results indicate that even after a brief series of ORG 2766 administration, there are changes in emotionality that may last for an extended period of time after the cessation of treatment.     

ACTH and ACTH4-10 modification of neophobia and taste aversion responses in the rat.

A series of experiments assessed the effects of ACTH and the ACTH analogue ACTH4-10 on drinking in conditioned taste aversion and neophobic situations. Both substances delayed the extinction of a conditioned taste aversion established by a single pairing of lithium chloride with milk (Experiment 1). However, in this situation, the ACTH parent peptide was more potent behaviorally. Administration of ACTH suppressed milk consumption in animals with no toxicosis experience (Experiment 2). This effect was apparently not due to the conditioning of a taste aversion (Experiment 3) with ACTH serving as a weak aversive unconditioned stimulus. Administration of exogenous ACTH (Experiment 4) or ACTH4-10 (Experiment 5) did not enhance neophobia; however, repeated injections of ACTH suppressed drinking. This ACTH suppression was related to the familiarity/novelty of the subtance being consumed. The neophobic response to milk eas no accompanied by pituitary-adrenal activation (Experiment 6). Both neophobic and conditioned taste aversion situation appear to be useful for assessing peptide effects on consummatory behavior.     

Imitation, social facilitation, and the effects of ACTH 4-10 on rats' bar-pressing behavior

The effects of ACTH 4-10 on rats' imitation learning was examined during the acquisition and extinction of a bar-press response for water reinforcement. Rats were exposed to either a bar-pressing conspecific (OB), an experimentally naive conspecific (ON), or an empty box (OE) during bar-press acquisition. In a factorial design, each rat was then exposed to one of the same three conditions during extinction. An 80 mcg dose of ACTH 4-10 was administered to half of the rats in each group prior to observation. Performance differences during acquisition were generally small, but significant performance differences during extinction were found. Social facilitation was indicated by the finding that rats extinguished in the presence of a conspecific exhibited significantly greater resistance to extinction than rats extinguished in the presence of an empty box. An imitation effect was also found. Rats that observed a bar-pressing conspecific during both acquisition and extinction (group OB-OB) showed significantly greater resistance top extinction than did groups OB-ON, CB-OE, or OE-OE. There were no significant effects of the hormone, however, relative to saline controls.     

Effects of BIM-22015, an analog of ACTH4-10, on functional recovery after frontal cortex injury.

Male rats, 90-100 days old, with frontal cortex lesions were given either subcutaneous sterile water (SW) as a vehicle control or 1, 10, or 100 micrograms of BIM-22015 every other day for 20 days. Brain-injured subjects tested in the Morris water maze with either 10 micrograms BIM-22015 or SW took significantly more trials than sham-operated rats to locate a submerged platform eight consecutive times within 60 s. The animals given 1 or 100 micrograms BIM-22015 took significantly fewer trials to reach criterion than brain-injured animals in the other drug treatment groups. On a percentage of savings, measured 8 days after reaching criterion, the brain-injured subjects given 1, 10, or 100 micrograms BIM-22015 did not differ from sham-operated rats. In contrast, the brain-injured animals given SW took longer to find the submerged platform than they did during the initial training. To assess long-term effects of the ACTH analog treatment, rats were trained on a delayed spatial alternation task 30 days after receiving the last injection. On this task, brain-injured rats treated with the 10-micrograms dose performed significantly better than those given sterile water. Acetylcholinesterase (AChE)-labeled neurons counted in the nucleus basalis magnocellularis indicated that rats with frontal cortex damage given the 10-micrograms treatment did not differ from the sham controls and had significantly more AChE-positive neurons than injured counterparts treated with SW or 100 micrograms.     

ACTH 4-9 analog can retard spatial alternation learning in brain damaged and normal rats

Thirty adult male hooded rats (Long-Evans strain) were assigned randomly to one of three lesion groups (n = 10) and prepared with medial frontal, posterior parietal, or sham neocortical injuries. Following a recovery interval of 10-12 days, access to water was limited to 30 min per day and the rats were shaped to traverse a T-maze for a reward of sweetened water. After a pretraining criterion was attained, osmotic minipumps (Alzet 2002) were installed subcutaneously. The minipumps delivered chronically for the next 14 to 15 days either 0 or 1.2 micrograms of ACTH 4-9 dissolved in bacteriostatic saline per day while the rats were trained on a reinforced spatial alternation task. Analysis of the number of errors made to a criterion of at least 80% correct alternations in two consecutive training sessions, or a ceiling of 62 errors (attained by two rats with parietal lesions), revealed that learning was impaired in the rats with parietal injuries. Contrary to our hypothesis, animals receiving ACTH 4-9 committed more errors than their counterparts receiving only saline.     

Delta-sleep inducing peptide (DSIP) and ACTH (4-10) analogue influence fos-induction in the limbic structures of the rat brain under emotional stress

The effects of the ACTH (4-10) analogue, ACTH (4-7)-Pro-Gly-Pro, and delta-sleep inducing peptide (DSIP) on the induction of Fos immunoreactivity in the hypothalamic parvocellular paraventricular nucleus (pPVN) and limbic brain regions were studied in Wistar rats with high (resistant) or low (predisposed) resistance to emotional stress, predicted from differences in their open-field behaviour. Fos-immunoreactive (Fos-IR) cells were counted in brain sections automatically with a computer-based image analyser. Under basal conditions, Fos-IR cell numbers were greater in the pPVN in the predisposed rats, but were lower than in the resistant rats in the basolateral amygdala and medial and lateral septum. Intraperitoneal DSIP injection (30 μg/kg) increased basal Fos-IR cell number in the pPVN and lateral septum in resistant rats, with no effects in predisposed rats. ACTH (4-10) analogue (50 μg/kg)increased Fos expression in the pPVN in both resistant and predisposed rats, with essentially no effects in the basolateral amygdala or medial and lateral septum. Emotional stress (60 min restraint and intermittent subcutaneous electrical shocks) increased Fos expression in the pPVN and medial and lateral septum similarly in predisposed and resistant rats, but in the basolateral amygdala in only the predisposed rats. Intraperitoneal DSIP injection reduced the increases in Fos-IR cell number after emotional stress, particularly in predisposed rats. In predisposed rats DSIP decreased the number of Fos-IR cells in the pPVN and the medial and lateral septum, with no change in the basolateral amygdala. In resistant rats, DSIP decreased Fos expression only in the lateral septum. ACTH (4-10) analogue injection inhibited stress-induced Fos expression in the pPVN and the medial septum, but only in predisposed rats. The experiments indicate that DSIP and ACTH (4-10) analogue reduce pPVN and limbic neurone responses to emotional stress in the rats predisposed to emotional stress; the effects on Fos expression may play a role in the biological activities of these peptides.     

Gender attribution and gender agreement in 4- to 10-year-old French children

Grammatical gender is generally considered an early and error-free acquisition in French children. This article first examines how children cope with the gender attribution problem, i.e., how they determine the gender of individual nouns. We consider the plausibility and requirements of an account in which tacit phonological assignment rules are put to use to solve attribution problems and contrast it with a simple “masculine as default” strategy. Elicited production data from three experiments, involving 312 4–10-year-old French children and 40 adult controls, were found compatible with this latter scenario and to provide only scant support for the former one. Second, we argue that previous studies have overestimated French children's gender agreement abilities, and that French children's ability to make the article and the adjective agree can be assumed from age 7 onwards, but not before.     

Exposure to a stressor produces a long lasting enhancement of fear learning in rats

In contextual fear conditioning, footshock is given in a context, and re-exposure to this context elicits the conditional defensive response of freezing, a reliable behavioral index of conditional fear. Normally, the amount of contextual freezing is directly proportional to the number of shocks an animal receives in the context. However, pre-exposure to a stressor can produce an enhancement in conditional freezing. Pre-exposure to repeated footshock in one context produces an enhancement of conditional freezing to cues associated with a single shock in a second distinct context. This model of stress-enhanced fear learning (SEFL) can be utilized to study how stress affects learning of future aversive events. The experiments in this paper characterize the magnitude and longevity of SEFL. In the first experiment, the number of footshocks given during the pre-exposure session was varied and conditional fear to the single shock was assessed. Pre-exposure to 1 shock did not produce an enhancement in fear learning in the second context, but pre-exposure to 4 or 15 shocks did. The time-course of the enhancement was examined in the next two experiments. These experiments show that SEFL persists for at least 3 months.     

Utilities in the 2-4-6 task

The Wason 2-4-6 task was embedded in a practical reasoning scenario where number sequences had well-defined utilities in the process of achieving a goal. Reasoners' hypothesis-testing behavior was clearly goal-driven and was significantly influenced by whether the utilities favored positive or negative sequences. In the version of the scenario where generating positive sequences had greater benefits than generating negative ones, participants performed poorly at the task as measured by their ability to guess the correct rule and by the nature and number of triples tested before making an announcement. In contrast, the scenario that assigned a greater utility to the production of negative sequences fostered significantly more diligent and creative hypothesis-testing behavior, and participants were significantly more likely to discover the rule. These results suggest that the poor performance observed in Wason's traditional 2-4-6 task reflects a hypothesis-testing process that by default assigns greater utility to the production of sequences that conform to the initial triple, and hence receive positive feedback. However, reasoners are not averse to producing negative sequences, and understand their implication, if their utility is made relevant in the process of achieving goals.     

Reorientation in a small-scale environment by 3-, 4-, and 5-year-old children

Geometric features of surfaces and local information are constitutive elements of spatial representations. A number of studies in animals (rats) and human children (24 months old) have shown that in a rectangular environment with a reward hidden in one of the corners, geometric properties predominate over local cues for search strategies. In contrast, monkeys and human adults are able to take into account both types of information (geometric and local) to reorient. So far, all of the experiments have been conducted in the locomotor space involving a navigational task. In the present study, we examined whether similar search patterns are found using a tabletop model of a rectangular room. Three groups of children (3-, 4-, and 5-year-olds) and one group of adults were tested. Results show that geometric encoding appears only at 4 years of age, that is later than in the locomotor space. The joint use of geometry and local cues emerges at 5 years of age. These data show that similar types of processing are implemented in both manipulatory and locomotor space but not at the same time. The difference between locomotor and manipulatory tasks suggests that being immersed in the environment makes this separated processing easier than being confronted by a task for which the object is exterior to the participant.     

Using a chaser to decrease packing in children with feeding disorders

Packing is a problematic mealtime behavior that is characterized by pocketing or holding solids or liquids in the mouth without swallowing. In the current study, we examined the effects of a chaser, a liquid or solid consistently accepted and swallowed by the child, to decrease packing of solid foods in 3 children with feeding disorders. During the chaser procedure, the therapist presented the chaser immediately for 2 children or 15 s after each bite presentation for 1 child. The chaser was effective in decreasing packing for all 3 children. The results are discussed in terms of the clinical importance of the findings and directions for future research.     

Using music to decrease disruptive vocalizations in a man with dementia

Music played through headphones was noted to reduce the disruptive chanting and speech‐like vocalizations of a 68‐year‐old man who lived in a secure dementia unit. We conducted a variety of assessment procedures, including a functional analysis ‘alone’ condition, to identify why this simple intervention may have been effective for this individual. The data suggest that music provided an alternative source of auditory stimulation to that produced by automatically reinforced vocal behavior. Copyright © 2010 John Wiley & Sons, Ltd.     

Autistic traits and neuropsychological performance in 6- to-10-year-old children: a population-based study

Clinical studies of children with autism spectrum disorder (ASD) provide evidence for poorer neuropsychological performance within specific domains compared to age, gender, and sometimes IQ-matched controls. Since recent evidence suggests that autistic symptoms form a spectrum that extends into the general population, it was our goal to evaluate the nature of the relationship between autistic traits and neuropsychological performance across the continuum in the general population. We examined neuropsychological performance across five different domains in 1019 6-to-10-year-old children participating in a population-based study of child development. Autistic traits were assessed when the children were 6 years of age using the Social Responsiveness Scale and ASD diagnoses were obtained via medical records. Neuropsychological functioning was measured using the NEPSY-II-NL and included the domains of attention and executive function, memory and learning, sensorimotor functioning, language, and visuospatial functioning. We found that children with higher autistic traits showed significantly lower neuropsychological performance in all domains investigated and that this association remained even after excluding children with the highest autistic traits or confirmed ASD. When comparing 41 children with confirmed ASD diagnosis to typically developing controls, children with ASD showed significantly lower neuropsychological performance across all domains. Taken together, our results suggest that children with both ASD and subclinical autistic traits have lower neuropsychological performance. Thus, this may provide an understanding of why some children without an ASD diagnosis may require some additional assistance within academic settings.     

Facilitation of extinction by an increase or a decrease in trial duration

Five experiments examined the effects of altering the duration of a conditioned stimulus (CS) for extinction. For the first 3 experiments, rats received conditioning with a 10-s CS before different groups received extinction with a CS that was either the same duration or longer than that used for conditioning. For the remaining 2 experiments, conditioning was conducted with a 60-s CS before different groups received extinction with a CS of either the same duration or a shorter duration than that used for conditioning. In all experiments, extinction progressed more readily when the CS duration was different for the 2 stages than when it was constant. The results are discussed in terms of rate expectancy theory and associative learning theory.     

Using a flipped spoon to decrease packing in children with feeding disorders

We evaluated the effects of redistribution and swallow facilitation with a flipped spoon on packing in 2 children with a feeding disorder. For both participants, packing decreased when we implemented the flipped spoon treatment package. Mechanisms responsible for behavior change and areas of future research are discussed.     

Behavioral contrast produced by a signaled decrease in local rate of reinforcement

Pigeons' key pecking in the presence of one stimulus (S1) was reinforced according to a response-dependent variable-interval schedule. Pecking rate during S1 increased (behavioral contrast) when a second stimulus (S2) [associated with either a response-dependent fixed-interval schedule (Experiment I) or a response-independent reinforcement schedule in which reinforcement availability was signaled by visual (Experiment II) or temporal (Experiment III) stimuli] alternated with S1. These experiments suggest that a discriminable, signaled decrease in local reinforcement rate during S2 is an antecedent of the behavioral contrast response rate increases during S1.     

Parents' description of conduct problems in their children - a test of the Eyberg Child Behavior Inventory (ECBI) in a Swedish sample aged 3-10

The Eyberg Child Behavior Inventory (ECBI) is a widely used 36-item uni-dimensional parent rating scale constructed to measure disruptive behavior problems in children. However, in an American sample a 22-item version, including three subscales, has been suggested in order to increase the usefulness of the ECBI. Two studies were conducted to test the ECBI in a Swedish sample (N = 841). The aims of Study I were (a) examine the psychometric properties of the ECBI (b) to investigate the correspondence between mothers' and fathers' ratings, and (c) to obtain Swedish norms. The aim of Study II was to test the suggested three-factor solution in the Swedish sample using a confirmatory factor analysis (CFA). The ECBI showed good psychometric properties also in the present study, and Swedish normative data is presented. The best-fitting CFA-model was identical to the previously suggested three-factor model, which thus might be a useful alternative to the 36-item version.