PUBLICACIONES RELEVANTES: 

BRITISH JOURNAL OF PSYCHOLOGY, 84, 119-132 (1993)
 Latent inhibition and recall/recognition of  irrelevant stimuli as a function of pre-
 exposure duration in high and low psychotic- prone normal subjects

 L.G. De la Casa and G. Ruiz
 University of Seville
 R. E. Lubow
 Department of Psychology, Tel Aviv University, Ramat Aviv 69978, Israel

Learning to ignore non-relevant stimuli (coloured geometric shapes) was evaluated in high and low psychotic-prone normal subjects in two experiments.  In the first, subjects were tested in a latent inhibition paradigm in a 2 x 2 x 3 factorial design (high vs. low psychotic proneness, as measured by MMPI subscales; pre-exposure of the stimuli such that they were non-relevant before the test but relevant in the test vs. absence of such pre-exposure; three levels of pre-exposure duration: 3-, 6and 15-min).  Low psychotic-prone subjects showed the latent inhibition effect (poorer learning as a result of pre-exposure to the non-relevant stimuli as compared to no pre-exposure) at 6- and 15-min durations, but not at 3-min.  High psychoticprone subjects failed to show latent inhibition at 3- and 6-min durations, but did show the effect at 15-min.  The second experiment employed a 2 x 3 design (high vs. low psychotic proneness; three levels of pre-exposure duration of the same stimuli used in Expt l). High psychotic-prone normal subjects recalled and recognized more previously non-relevant stimuli than low psychotic-prone subjects, particularly after 6-min pre-exposure to those stimuli. The data of the two experiments suggest that the attenuation of latent inhibition in high psychotic-prone subjects as compared to low psychotic-prone subjects is a result of the increased attention to non-relevant information.

BIOLOGICAL PSYCHIATRY 707(33), 707-711 (1993)
 Amphetamine-Produced Attenuatíon of Latent  Inhibition Is Modulated by Stimulus Preexposure  Duration: Implications for Schizophrenia

 L. G. De la Casa, G. Ruiz, and R. E. Lubow 

The relationship between amphetamine-produced dopamine overreactivity and attention lo irrelevant stimuli is reflected in an attenuated latent inhibition (LI) effect.  This occurs in both animal and human subjects.  The present study examines the manner in which this effect in rats is modulated by the duration of stimulus preexposure, A factorial design was used with three levels of stimulus preexposure duration and either amphetamine or saline administration. In addition, there were corresponding groups that did not receive stimulus preexposure. It was found that althotugh amphetamine did indeed abolish Ll at short exposure intervals (30 sec), the Ll effect was normal for long stimultus preexposure didrations (150 sec).  The data were discussed in terms of the affects of amphetamine on the processing of irrelevant stimuli and the relationship of such a dysfunctional attentional process lo schizophrenia.

Key Words: latent inhibition, amphetamine, dopamine, schizophrenia

NEUROBIOLOGY OF LEARNING AND MEMORY 64, 125 -132 (1995)
 Latent lnhibition in Conditioned Taste Aversion: The Roles  of Stimulus Frequency and Duration and the Amount  of Fluid lngested during Preexposure

 GONZALO DE LA CASA* AND R. E. LUBOW** 
 *University of Seville, Seville, Spain; ** Department of Psychology, Tel Aviv   University,
 Ramat Aviv 69978, Israel

 Two experiments examined the effects of total stimulus preexposure on latent inhibition (LI) in a conditioned taste aversion procedure with rats.  Experiment 1 varied the frequency and duration of saccharin preexposures.  LI was an increasing function of the product of frequency x duration.  Experiment 2 kept saccharin exposure time constant but varied the amount of saccharin consumed by manipu lating number of hours of fluid deprivation prior to exposure.  Deprivation schedule conditions affected the amounts consumed which, in turn, modulated Ll magnitude, at least with a 1-day acquisition-test interval, as in Experiment 1. The data clearly indicate that LI is a function of total amount of contact with the preexposed saccha rin solution.  In addition, half of the subjeets in Experiment 2 were tested 21 days after the conditioning event.  LI was not present in any group tested at this interval. These data were discussed in regard to the controversy regarding whether LI represents a failure to acquire the CS-US association or a failure to retrieve that association.

 The present study describes two experiments designed to evaluate the attentional strategies that Type-A subjects use depending on the kind of task they have to solve.  The results indicate they embarked on two different strategies depending on the way in which the task was displayed: when two tasks were presented, one as important and the other as trivial, Type-A subjects focused their attention on the stimuli of the important task.  However, if a single task is presented and it appears simultaneously with some other stimuli for which there are no instructions, thus generating an ambiguous situation, the attentional strategy that appears in Type-A subjects could be called hypervigilance (defined as sustained attention directed at all stimuli involved in a task).  Anyway, both strategies are in consonance with the general aim of Type-A subjects to employ as much effort as possible in all the tasks they must solve. 1998 Elsevier Science Ltd.  All rights reserved
Key- Words: Type-A behavior pattern, attention, memory.

ESTUDIOS DE PSICOLOGÍA 53, 15-24 (1995)
 I. P. Pavlov, la actividad nerviosa superior y la psicología

 L. GONZALO DE LA CASA, GABRIEL RUIZ
 Y NATIVIDAD SÁNCHEZ
 Universidad de Sevilla

 En el presente trabajo se realiza un análisis histórico de la obra del reflexólogo I.P. Pavlov en el que sepersiguen tres objetivos fundamentales: el primero es tratar de describir el cambio de Intereses que, durante los primeros años del siglo XX, se produce en las investigaciones llevadas a cabo por Pavlov y sus colaboradores desde el estudio de los procesos digestivos al estudio de la actividad nerviosa superior. En segundo lugar, analizamos teoría pavloviana incidiendo en su alto grado de sistematización. Por último, reflejamos el interés mostrado por Pavlov ante la psiquiatría, interés que se hace patente en sus opiniones y debates con algunos de los más prestigiosos psiquiatras de su época. En este sentido se abordan las consideraciones que de las aportaciones realizadas por Janet, Freud y Schilder realíza Pavlov.
Palabras clave: Historia de la Psicología, Pavlov, Reflexología, Activídad Nerviosa Supenor, Psiquiatría.