Amnesia by post-training infusion of glutamate receptor antagonists into the amygdala, hippocampus, and entorhinal cortex.

The blockers of glutamate receptors, aminophosphonovaleric acid (AP5) (5.0 micrograms) and cyano-nitroquinoxaline-dione (CNQX) (0.5 microgram), were infused bilaterally into the amygdala, dorsal hippocampus, or entorhinal cortex of rats through indwelling cannulae 0, 90, 180, or 360 min after step-down inhibitory avoidance training. Animals were tested for retention 24 h after training. In the amygdala or hippocampus, AP5 was amnestic when given 0 min after training and CNQX was amnestic when given 0, 90, or 180 min after training. In the entorhinal cortex, AP5 was amnestic when given 90 or 180 min after training and CNQX had no effect. The results suggest that a phenomenon sensitive first to AP5 and then to CNQX in the amygdala and hippocampus, probably long-term potentiation (LTP), is crucial to post-training memory processing. LTP in these two structures could underlie their role in memory consolidation and could explain the late involvement of the entorhinal cortex in post-training memory processing.     

The necessity of theology and the scientific study of religious beliefs

An earlier version of this paper was prepared for a University of New England Social Sciences Seminar on ‘Religion and the Social Sciences’, organized by Professor of Philosophy peter forrest, to which it was presented on 14 June 1989.     

Satiation or availability? Effects of attention,memory, and imagery on the perception of ambiguous figures

The prolonged-inspection technique has been used to demonstrate effects of satiation on the perception of ambiguous figures. We propose that the inspection phase, in which subjects view an unambiguous version of the stimulus prior to observing the ambiguous figure, does not create neural fatigue but rather provides a context in which the alternative percept is apprehended and gains perceptual strength through processes such as imagination or memory. The consequent availability of the alternative organization drives the perceptual phenomena that have been thought to reflect satiation. In Experiment 1, we demonstrated that (1) preexperimental exposure to the target figures and (2) allocation of attention to the-inspection figures-were both necessary in order to obtain results similar to those predicted by the satiation model. In Experiment 2, we obtained similar results, finding that effects of prior inspection were greater the greater the amount and availability of information regarding the alternative percept during the inspection phase. Subjects who generated visual images of the noninspected alternative during inspection yielded results comparable to those from subjects to whom both versions were presented isuaily.     

“Was Maslow an Aristotelian?” Revisited

The Psychological Record - It is argued that in the formulation of his health and growth psychology Maslow was not inspired by Aristotelian philosophy but rather by Kurt Goldstein. A close study of...     

Processing level and recognition: A search method for inducing alternative encodings of unrelated words

Twenty-four subjects viewed cards containing four words. In synonym orienting, half of the cards contained a synonym pair and half did not; in homophone orienting, half of the displays contained a homophone pair. The remaining two words in each display were used to index retention. During presentation of displays, subjects responded “yes” or “no” to indicate the presence or absence of a matching pair. Following presentation, a recognition test was administered. Half the items were tested early and half were tested late; within each test order, half the items appeared with context cues during testing and half appeared without. Results showed superior recognition (1) following semantic orienting, (2) for items tested early, (3) for items tested with context, and (4) for nonmatch displays requiring exhaustive item comparison. An Orienting by Test Cuing interaction showed that the presence of test cues improved recognition for homophone orienting items only. The interaction may have resulted from the lack of cuetarget associations and the reinstatement of the phonemic orienting set during the test.     

Systems analysis of the integrative activity of the neuron

This article is aimed at revising the traditional concept of neuronal activity based on preeminence of transmembrane potentials and “electric summation” on the neuron surface. It presents a historical survey of the emergence of the prevailing concept on propagation of potentials alongconductive structures and reveals the psychological situation that determined the transfer of this concept to dendrites and the neuronal soma. Structural and biophysical properties of the neuron which do not permit information propagation along the neuronal membrane without crude distortion are critically discussed in detail.     

A note on the reliability of subjective judgment in discerning when the mouth is clear of salt taste stimuli

The ability of Ss to judge by taste when they had expectorated exogenous NaCl from the mouth was tested using 10 Ss. It was found that, after a 1-M salt mouthrinse, Ss judged its taste to have vanished while there were still residuals remaining in the mouth, which would have been detected by taste at preexperimental adaptation levels. This means that Ss are unable to judge for them selves when the mouth is clear of exogenous stimuli and that intertrial procedures requiring Ss to do this are suspect.     

The solution of anagrams: A reexamination of the effects of transition letter probabilities,letter moves,and word frequency on anagram difficulty

Word frequency (WF), number of letter moves, and solution word transition letter probabilities (TP) were related to anagram solution. The solution word TP measure was based on the relative frequencies of correct to incorrect bigrams within the pool of bigrams defined by the letters of the anagram rather than on the absolute frequencies of the correct bigrams. This bigram rank measure, which also took word length and letter position into account, was a powerful predictor of anagram difficulty (p < .001). Likewise, number of letter moves predicted anagram solution strongly (p < .001), but WF was only a marginal predictor (.05 < p < .10). In addition, there were no significant interactions among the three variables, nor wasanagram TP consistently related to anagram difficulty. The results were interpreted in terms of an approach which combined elements of an hypothesis and an S-R mediational theory.