The touchscreen cognitive testing method for rodents: how to get the best out of your rat

The touchscreen testing method for rodents is a computer-automated behavioral testing method that allows computer graphic stimuli to be presented to rodents and the rodents to respond to the computer screen via a nose-poke directly to the stimulus. The advantages of this method are numerous; however, a systematic study of the parameters that affect learning has not yet been conducted. We therefore sought to optimize stimuli and task parameters in this method. We found that when parameters were optimized, Lister Hooded rats could learn rapidly using this method, solving a discrimination of two-dimensional stimuli to a level of 80% within five to six sessions lasting ~30 min each. In a final experiment we tested both male and female rats of the albino Sprague-Dawley strain, which are often assumed to have visual abilities far too poor to be useful for studies of visual cognition. The performance of female Sprague-Dawley rats was indistinguishable from that of their male counterparts. Furthermore, performance of male Sprague-Dawley rats was indistinguishable from that of their Lister Hooded counterparts. Finally, Experiment 5 examined the ability of Lister Hooded rats to learn a discrimination between photographic stimuli. Under conditions in which parameters were optimized, rats were remarkably adept at this discrimination. Taken together, these experiments served to optimize the touchscreen method and have demonstrated its usefulness as a high-throughput method for the cognitive testing of rodents.     

French normative data and naming times for action pictures

The aim of the present study was to provide French normative data for 112 action line drawings. The set of action pictures consisted of 71 drawings taken from Masterson and Druks (1998) and 41 additional drawings. It was standardized on six psycholinguistic variables—that is, name agreement, image agreement, image variability, visual complexity, conceptual familiarity, and age of acquisition (AoA). Naming latencies to the action pictures were collected, and a regression analysis was performed on the naming latencies, with the standardized variables, as well as with word frequency and length, taken as predictors. A reliable influence of AoA, name agreement, and image agreement on the naming latencies was observed. The findings are consistent with previous published studies in other languages. The full set of these norms may be downloaded fromwww.psychonomic.org/archive/.     

Developmental changes in children's inductive inferences for biological concepts: implications for the development of essentialist beliefs

We examined developmental changes in children's inductive inferences about biological concepts as a function of knowledge of properties and concepts. Specifically, 4‐ to 5‐year‐olds and 9‐ to 10‐year‐olds were taught either familiar or unfamiliar internal, external, or functional properties about known and unknown target animals. Children were asked to infer whether each of four probes, varying in categorical and perceptual similarity to the target, also shared that property. Overall, children made more inferences for known concepts and familiar properties. Older children were more likely to use categorical than perceptual information when making inferences about internal and functional properties of known concepts; however, younger children, in general, made no distinction for property type, and they weighted categorical and perceptual information similarly. Both age groups utilized appearance when making inferences about external properties. Results are discussed in terms of developmental changes in children's appreciation of essentialism. Copyright © 2010 John Wiley & Sons, Ltd.     

Effectiveness of Group Music Therapy in a Psychiatric Hospital: A Randomized Pilot Study of Treatment Outcome

Individuals receiving inpatient psychiatric care (n = 32) were randomized to receive either brief music therapy or group therapy that constitutes the current standard of care (SOC), and completed measures of depression, mood, quality of life (QOL), and hope pre- and post-intervention. Group dynamics were evaluated by the therapists. Results indicate that significantly more patients in the music therapy group showed an increase in QOL than those in the SOC group. Regarding group dynamics, the music groups scored significantly higher on conflict and significantly lower on avoidance. Results of this study suggest that group music therapy in inpatient psychiatric settings may be as effective as SOC groups, more effective at impacting QOL, and more effective for particular diagnostic populations. Further research is needed to fully understand the impact of music therapy in this setting.     

Decision-making processes: sensitivity to sequentially experienced outcome probabilities

A computerized sequential event sampling decision-making task was administered to 187 5- to 10-year-olds and adults Participants made a series of choices between alternatives that differed in win probability (Study 1) or win and loss probability (Study 2). Intuitive and more explicit measures were used. Study 1 revealed that, across ages, participants demonstrated intuitive sensitivity to probability; however, adult participants evidenced greater sensitivity than did children, and younger children failed to demonstrate more explicit understanding of probability. Study 2 also revealed that children were intuitively sensitive to probability; however, the inclusion of loss had limited impact on decision processes. These findings and their relevance to cognitive developmental theory are discussed.     

Perirhinal cortex resolves feature ambiguity in configural object recognition and perceptual oddity tasks

The perirhinal cortex (PRh) has a well-established role in object recognition memory. More recent studies suggest that PRh is also important for two-choice visual discrimination tasks. Specifically, it has been suggested that PRh contains conjunctive representations that help resolve feature ambiguity, which occurs when a task cannot easily be solved on the basis of features alone. However, no study has examined whether the ability of PRh to resolve configural feature ambiguity is related to its role in object recognition. Therefore, we examined whether bilateral excitotoxic lesions of PRh or PPRh (perirhinal plus post-rhinal cortices) in the rat would cause deficits in a configural spontaneous object recognition task, and a configural simultaneous oddity discrimination task, in which the task could not be solved on the basis of features, but could only be solved using conjunctive representations. As predicted by simulations using a computational model, rats with PPRh lesions were impaired during a minimal-delay configural object recognition task. These same rats were impaired during a zero-delay configural object recognition task. Furthermore, rats with localized PRh lesions were impaired in a configural simultaneous oddity discrimination task. These findings support the idea that PRh contains conjunctive representations for the resolution of feature ambiguity and that these representations underlie a dual role for PRh in memory and perception.     

Dissemination of psychoactive substance information by innovative drug users.

Internet-based drug information may be relayed by innovative drug users, a group of individuals who use the web to learn about a new drug, experiment with that substance, and then disseminate their knowledge and experiences to others. We investigated the mechanisms adopted by innovative drug-using adolescents to distribute Internet drug information and experiences to peers, the size and geographic distribution of the receiving group, and the age at which innovative drug users began to disseminate drug information. Method: Cross-sectional survey of adolescents recruited by a respondent-driven sampling method. Of 18 innovative drug users, 17 reported using instant messaging (IM) to disseminate drug information and experiences to peers. The average age at which respondents adopted IM for this purpose was 16 years. Fifteen of 17 described using a distribution list with as many as 200 individuals who received only drug information. Ten respondents instant messaged drug information to online peers greater than 250 miles distant; nine respondents attached links to online drug resources (including www.erowid.org). This study has identified that IM plays an important role in the dissemination of Internet-based drug information by individual innovative drug users into larger social networks. Pediatricians should consider assessing IM use in drug abuse evaluations and recommending that parents of children with drug abuse problems should consider suspending IM services as a means of truncating the delivery of reinforcing drug information.     

VIDEO MODELING BY EXPERTS WITH VIDEO FEEDBACK TO ENHANCE GYMNASTICS SKILLS

The effects of combining video modeling by experts with video feedback were analyzed with 4 female competitive gymnasts (7 to 10 years old) in a multiple baseline design across behaviors. During the intervention, after the gymnast performed a specific gymnastics skill, she viewed a video segment showing an expert gymnast performing the same skill and then viewed a video replay of her own performance of the skill. The results showed that all gymnasts demonstrated improved performance across three gymnastics skills following exposure to the intervention.     

Muscimol,AP5, or scopolamine infused into perirhinal cortex impairs two-choice visual discrimination learning in rats

The perirhinal cortex (PRh) has been strongly implicated in object recognition memory and visual stimulus representation. Studies of object recognition have revealed evidence for the involvement of several neurotransmitter subsystems, including those involving NMDA (N-methyl-d-aspartic acid) and muscarinic cholinergic receptors. In the present study, we assessed the possible involvement of PRh and related receptor subsystems in two-choice visual discrimination learning by Lister Hooded rats tested in touchscreen-equipped operant boxes. In Experiment 1, daily pre-training inactivation of PRh with the GABA_A receptor agonist muscimol (0.5 μg/hemisphere) significantly impaired acquisition of the two-choice visual discrimination. In Experiment 2, daily pre-training blockade of either NMDA or muscarinic receptors in PRh with AP5 (5.9 μg/hemisphere) or scopolamine (10 μg/hemisphere), respectively, impaired task acquisition. These results parallel the findings from object recognition studies and suggest a generality of neurotransmitter receptor involvement underlying the role of PRh in both object recognition memory and visual discrimination learning. The involvement of PRh in both types of tasks may be related to its role in complex visual stimulus representation.