2-Deoxy-d-Galactose Effects on Passive Avoidance Memorization in the Rat

2-Deoxy-d-galactose (do-gal) hinders glycoprotein fucosylation. This compound was intracerebroventricularly administered to male adult Wistar rats in order to assess whether it could exert amnesic effects on a passive avoidance response (PAR) to be learned in the light–dark box apparatus. Three experiments were performed. In the first, do-gal was administered immediately after the acquisition trials at three dosages (2, 4, and 8 μmol). It was found that only the 4-μmol dosage was followed by PAR disruption. In the second, do-gal was administered at the adequate dosage (4 μmol) either 30 min before the acquisition trial or 30 min before retrieval testing. It was found that only the preretrieval administration was followed by PAR impairment. In the third, do-gal (4 μmol) was administered in postacquisition, at increasing postacquisition delays (0.25, 1.5, 4, and 6 h). It was found that there was PAR disruption only after do-gal administration at the shortest (0.25 h) delay. The results confirm that in the rat, glycoprotein fucosylation is involved in some of the phases of memory trace processing, and they are discussed in relation to other findings in the rat and the chick.     

成人日常问题解决的老化研究

日常问题解决能力是近十几年来老年心理学中研究比较活跃的一个领域。本文介绍了有关日常问题解决研究的四种理论,即心理测量的智力内隐理论、形式后思维的辨证思维理论、信息加工理论和社会认知与智慧理论,及其初步的研究成果,并进一步指出在理论上整合和在实践中开展干预的研究方向。     

Footshock intensity and generalization in contextual and auditory-cued fear conditioning in the rat

The relationship between US (footshock) intensity and the two conditioned freezing responses (to acoustic CS and to "context") was investigated in fear conditioning. Administered footshock intensity was 0.00, 0.15, 0.30, 0.60, 0.90, and 1.20 mA to six different groups of 70-day-old male Albino Wistar rats. To measure contextual freezing, the animals were again placed inside the conditioning apparatus without acoustic CS and US presentation. To measure acoustic CS freezing, the animals were placed in a totally different apparatus and only the acoustic CS was presented. The 0.15 mA footshock intensity was not sufficient to condition the animals, in fact no freezing was exhibited as in the non-shocked control group. The 0.30 mA footshock intensity was sufficient only to condition the animals to the acoustic CS, whereas the 0.60 mA was sufficient to condition the animals both to acoustic CS and to context. Footshock intensities (0.90 and 1.20 mA) did not elicit any significant increase in conditioned freezing for either acoustic CS or context but at the highest one the generalization phenomenon appeared (freezing in the different context before presentation of acoustic CS). Acoustic CS freezing to all over-threshold intensities was longer than that to context. In conclusion, freezing responses to acoustic CS and context after increasing footshock intensities follow distinct patterns, and intermediate footshock intensities (0.60 and 0.90 mA) appear to be the most useful for eliciting conditioned freezing responses to acoustic CS and to context without inducing a generalized fear status contamination.     

Pituitary adenylate cyclase-activating polypeptide hormone (PACAP) at very low dosages improves memory in the rat

To ascertain whether very low dosages of pituitary adenylate cyclase-activating polypeptide (PACAP) influence learning in mammals, immediately after the acquisition trial of a passive avoidance response (PAR) paradigm, PACAP-38 was administered intracerebroventricularly at increasing dosages (0, 0.02, 0.2, 2, 20, and 200 ng in 10 microl saline) to different groups of rats. The mnemonic effects were measured by means of retention testing 48 and 96 h later. At intermediate PACAP-38 concentrations there was a significant mnemonic improvement of the PAR. The maximal effect was observed after the 0.2-ng PACAP-38 administration (longer step-through latencies). There was a lesser effect at the subsequent higher concentration, 2 ng. Higher dosages had no effects. It is concluded that PACAP-38 acts as an enhancer of mammalian mnemonic processes even at very low dosages. The positive effect follows an inverted U-shaped dose-response curve. The results may be of interest for the therapy of some neuropathological conditions.     

Attachment as an informative relationship

Levels of awareness, a personal construct concept that explains varying levels of "consciousness" while respecting the felt experience of the client, has not been systematically explored within the personal construct literature. Six processes associated with varying levels of awareness are discussed in this article: (1) ways the client's meaning system may preclude possibilities experienced by the therapist, (2) implications of the system that have not been elaborated, (3) terror associated with exploring the contrast poles to meanings, (4) framing assumptions that limit our awareness of issues, (5) suspended events and the shutting down of meaning-making, and (6) nonverbal construing. These processes have implications for how the clinician will connect with and engage the creativity of the client.     

Schizophrenia and paranoia as solutions to predictive failure

Abstract

Paranoia and schizophrenia represent two opposite ways of reacting to invalidation. In paranoia the system tends to become more and more monolithic. Whenever the paranoid individual's observations contradict his or her personal theory, the theory prevails, so that the system evolves toward an “exaggerated dogmatism.” In the schizophrenic syndrome, on the other hand, we find renunciation of a unitary organization of knowledge. In this form of an “exaggerated empiricism,” the system moves toward fragmentation, and predictions become variable and contradictory. The path that is followed depends on the premorbid structure of the individual's system and the particular kind of invalidation experienced.