(-)-9-Dehydrogalanthaminium bromide,a new cholinesterase inhibitor,enhances place and object recognition memory in young and old rats

In a previous study, we showed that (-)-9-dehydrogalanthaminium bromide, a synthetic galanthamine derivative, was more potent than galanthamine in inhibiting acetylcholinesterase. We studied here the action of this new compound on recognition memory in young and old rats, using a two-trial recognition task designed to test both place and object recognition. (-)-9-dehydrogalanthaminium bromide was injected (0.3, 1, and 3 mg/kg, i.p.) in young and old rats before the acquisition phase, immediately after it, or before the retrieval phase of the task, in order to determine the stage of information processing affected by the compound. (-)-9-dehydrogalanthaminium bromide improved both place and object recognition in young rats, via an enhancement of acquisition (3 mg/kg: place recognition; 1 and 3 mg/kg: object recognition) and consolidation (1 and 3 mg/kg) information processing. In old rats, (-)-9-dehydrogalanthaminium bromide improved performance by acting on the acquisition processes of place (0.3, 1, and 3 mg/kg) and object (1 and 3 mg/kg) recognition. These results provide information on the profile of activity of (-)-9-dehydrogalanthaminium bromide on memory processes, and suggest that this new compound could have utility in the treatment of cognitive dysfunction occurring in Alzheimer's disease or in the normal course of aging.     

Peripheral 8-OH-DPAT and scopolamine infused into the frontal cortex produce passive avoidance retention impairments in rats

The present study determined whether peripheral injections of the 5HT(1A) agonist (8-OH-DPAT), scopolamine infusions into the frontal cortex, or a combination of both drug treatments would produce impairments in rats trained on passive avoidance. Using a 2x2 design, rats were infused with either bacteriostatic water or 30 microg/1 microl of scopolamine HCl into the frontal cortex 30 min before being trained on passive avoidance. This was followed by injections (ip) of either 0.1% ascorbic acid/bacteriostatic water or 30 microg/kg of 8-OH-DPAT 15 min later. All subjects were tested for retention 72h later. At test, the initial latency to enter into the black shocked compartment and the total time spent in the white safe compartment (TTW) were recorded. Analysis of the latency data indicated that scopolamine and 8-OH-DPAT, when administered singly or in combination, produced amnesia for the task. Assessment of TTW scores, however, revealed that of the three drug-treated groups, only animals treated with 8-OH-DPAT alone tended to avoid the previously shocked black compartment and spend more time in the white safe compartment. These data indicate that either stimulating 5-HT(1A) or blocking frontal cortical muscarinic receptors at training impairs passive avoidance performance and that the deficit following the latter treatment is somewhat more extensive. Implications for the role frontal cortical muscarinic and 5HT(1A) receptors play in learning and memory are discussed.     

Are discrepancies among child,mother, and father reports on children's behavior related to parents' psychological symptoms and aspects of parent-child relationships?

Examined whether parents' symptoms and qualitative and quantitative aspects of parent–child relationships make unique contributions to mothers' and fathers' reports of, and mother–child, father–child, and father–mother discrepancies on, children's behavior. Participants were 100 children, aged 10–12, and their mothers and fathers. Parents' symptoms and parent–child relationships made unique contributions to both parents' ratings of externalizing behavior. Although parent–child relationship variables were related to both parents' ratings of internalizing behavior, only parents' symptoms made unique contributions. On mother–child and father–child discrepancies, differences emerged between mother and father, and internalizing and externalizing behaviors. Both fathers' and mothers' symptoms contributed to father–mother discrepancies on both behavior types, with parent–child relationships contributing unique variance to discrepancies on internalizing behavior. Results highlight the importance of each informant's symptoms and relationship variables in understanding informant discrepancies.     

Acquisition and automatization of a complex task: an examination of three-ball cascade juggling

The learning patterns of 3-ball cascade juggling from acquisition until automaticity were examined in 10 participants. On the basis of outcome measures derived from 26 practice sessions and 4 periodic probe sessions, the authors differentiated participants into 3 distinct learning types: a proficient group, an emerging group, and a single late learner. The proficient group was distinguished by how rapidly they learned and automatized performance. Most interesting, an inverse response cost (i.e., performance boost) on the secondary task was found in the majority of proficient group members during the dual-task condition. The present results are discussed in relation to the P. L. Ackerman model (1987, 1988) of complex skill acquisition as is the significance of the inverse response cost finding.     

Scores on the eysenck personality questionnaire for a sample of children and adolescents receiving psychological treatment in Puerto Rico

Personality questionnaire scores obtained by children and adolescents (n = 28) receiving psychological treatment at a health facility in Humacao, Puerto Rico were examined. The scores were compared with those of regular school children of the same age, of Gurabo, Puerto Rico, who were not in treatment (n = 30). The children in treatment obtained higher scores on Psychoticism, lower scores on Extraversion, and similar scores on Neuroticism and Dissimulation by comparison with regular students.     

Effects of age on measures of complex working memory span in the beagle dog (Canis familiaris) using two versions of a spatial list learning paradigm

The present study used two versions of a spatial list learning (SLL) paradigm to examine the effects of increased cognitive load on visuospatial working memory processes in young and old beagle dogs. In the first experiment, young, and a select group of old dogs were first presented with one item, then two, and then three, and were rewarded for responding to the novel position. The dogs were able to learn the task at short delays, but compared with young dogs, old dogs performed worse at delays of 10 sec, and could not reach longer delays. Analysis of errors indicated that memory was best for end items in the spatial list and that within sessions, the number of errors in later trials was greater than the number of errors in earlier trials. A second version of the task, a modified SLL (mSLL) was developed to control for the use of non-mnemonic strategies on the SLL task. In this version, the first two items were presented individually. Acquisition and maximal memory performance were better in the young relative to the old dogs. Similar to the original SLL design, memory for early list items was worse than memory for later list items in both young and old dogs. The within-session pattern of errors however, did not change from trial to trial on the mSLL. The present results suggest that multiple working memory processes are engaged during complex tests of visuospatial function and the neuroanatomical substrates controlling these processes are affected differentially by age in the beagle dog.     

Activation of the cannabinoid receptor type 1 decreases glutamatergic and GABAergic synaptic transmission in the lateral amygdala of the mouse

The endogenous cannabinoid system has been shown recently to play a crucial role in the extinction of aversive memories. As the amygdala is presumably involved in this process, we investigated the effects of the cannabinoid receptor agonist WIN 55,212-2 (WIN-2) on synaptic transmission in the lateral amygdala (LA) of wild-type and cannabinoid receptor type 1 (CB1)-deficient mice. Extracellular field potential recordings and patch-clamp experiments were performed in an in vitro slice preparation. We found that WIN-2 reduces basal synaptic transmission and pharmacologically isolated AMPA receptor- and GABA_A receptor-mediated postsynaptic currents in wild-type, but not in CB1-deficient mice. These results indicate that, in the LA, cannabinoids modulate both excitatory and inhibitory synaptic transmission via CB1. WIN-2-induced changes of paired-pulse ratio and of spontaneous and miniature postsynaptic currents suggest a presynaptic site of action. Inhibition of G_i/o proteins and blockade of voltage-dependent and G protein-gated inwardly rectifying K⁺ channels inhibited WIN-2 action on basal synaptic transmission. In contrast, modulation of the adenylyl cyclase-protein kinase A pathway, and blockade of presynaptic N- and P/Q- or of postsynaptic L- and R/T-type voltage-gated Ca²⁺ channels did not affect WIN-2 effects. Our results indicate that the mechanisms underlying cannabinoid action in the LA partly resemble those observed in the nucleus accumbens and differ from those described for the hippocampus.     

Perceptual inertia: spatial attention and warning foreperiod?

Perceptual inertia refers to a potential explanation for the observation that during a short period after stimulus onset, the visual system is insensitive to discriminatory detail. The present study attempted to replicate this empirical result in a simple one-item letter-identification task. The results provided little if any support for the construct of perceptual inertia. In the five experiments reported, evidence consistent with perceptual inertia was only obtained in Experiment 5. However, the Experiment 5 results can at least equally parsimoniously be explained in terms of two standard explanatory factors: an effect of precuing of the target position (selective attention) and foreperiod duration (general preparation). Received: 27 September 1999 / Accepted: 11 February 2000     

On the Independent Roles of Cognitive & Political Sophistication: Variation Across Attitudinal Objects

People are motivated to maintain consistency between importantly held identities, preferences, and judgments. In political contexts, motivated reasoning can help explain a wide range of political phenomena, including extremism, polarization, and misperceptions. However, recent findings in psychology have challenged this account. These perspectives emphasize the role of cognitive sophistication (e.g., analytical reasoning, numerical literacy) in political attitudes, but differ in terms of whether it is expected to attenuate or exacerbate politically motivated reasoning and belief in conspiracy theories. Yet prior investigations have not examined the relative and independent effects of both political and cognitive sophistication. Using data from two samples, including one sampled to approximate representativeness in the U.S., we demonstrate that both types of sophistication have independent and (at times) countervailing effects on belief in COVID-19 conspiracy theories and other political attitudes. Our results are critical for theories of cognitive sophistication, political cognition, and attitudes, and the psychology of conspiracy theories.