THE USE AND IMPACT OF PSYCHOLOGY IN VENEZUELA: TWO EXAMPLES

Two cases are presented to illustrate how psychological knowledge and technology have been used in Venezuela. The first case relates to the use of psychological technology in Venezuelan politics where it is possible to identify a change from “caudillismo” to a more democratic “voting against” political culture. There is evidence that imported political compaigning techniques and extensive use of polling have been a factor of some importance in such change. The second case refers to the activities of the Minister for the Development of Intelligence, who has started a group of projects to improve cognitive functioning in different age groups. These programs are too recent to ascertain their effectiveness; so data is reported on an opinionative evaluation of one of the projects, carried out among Venezuelan psychologists and pediatricians.     

Selective changes of sensitivity after adaptation to simple geometrical figures

Using simple geometrical figures, the effect of adaptation upon sensitivity to figures of the same or different form was investigated. The adapting stimuli (blank white field, contour triangles, or circles) were presented for 1, 5, 30, or 60 sec. The test stimuli were always triangles, presented for a short exposure time at .1, .2, .4, .8, and 1.2 sec after the offset of the adapting pattern. The threshold duration of the test stimuli was measured. It was found that both adapting patterns raised the threshold above that measured for adaptation with the blank white field. But it wss only for the pair “adapting triangles-test triangles” that an increase of the time of adaptation beyond 5 sec resulted in an increase of this effect. This suggests that selective lowering in sensitivity during prolonged viewing of some figures may develop. The effect disappeared after about 1.2 sec following an exponential curve.     

Biochemistry of nervous dogs

Previous behavioral studies on a nervous strain of pointer dogs have demonstrated genetic as well as environmental components in the nervous trait. Behaviorally these animals are extremely hypervigilant, with an apparent low threshold to fear and show strong avoidance of humans. In addition, the nervous E strain dogs show an unusually high degree of sensitivity to the mange mite. These observations led to the initiation of studies to determine whether differences exist between the normal A strain and the E strain of dogs at the biochemical level. Although a number of biochemical parameters examined have shown no statistically significant difference between the two strains, the modification of serum creatine phosphokinase (CPK) activity in response to various types of stress does differ as a function of strain—the nervous dogs being less, not more, responsive than the healthy dogs. When not specifically subjected to stress the serum CPK levels in both strains were highly related to age. Significant differences between strains also have been demonstrated in the cerebrospinal fluid acetyl cholinesterase activity levels in older animals. Tryptophan loading experiments, conducted in the presence and absence of the monoamine oxidase inhibitor, tranylcypromine, resulted in no readily observable behavioral modification of either strain and the response of the cerebrospinal fluid 5-hydroxyindoleacetic acid levels was similar for the two strains.     

Prenatal cortisol, prematurity and low birthweight

Three hundred depressed pregnant women were recruited at approximately 20 weeks gestation. They were then divided by a median split into high and low urinary cortisol level groups. The high cortisol group had higher CES-D depression scores and higher inhibition (BIS) scores prenatally. Their fetuses had smaller head circumference, abdominal circumference, biparietal diameter and fetal weight. The high cortisol group neonates were shorter gestational age and lower birthweight and they had lower Brazelton habituation and higher Brazelton reflex scores. Discriminant function analyses suggested that cortisol levels more accurately classified short gestation and low birthweight groups than CES-D depression scores.     

Happy faces are habituated more slowly by infants of depressed mothers

Three-month-old infants of depressed (n=16) and non-depressed mothers (n=16) were habituated to video clips of a female model reciting phrases while posing happy or sad facial/vocal expressions and dishabituated to the alternate expressions. Overall, infants of depressed mothers took longer to habituate the video clips compared to infants of non-depressed mothers, and those assigned to habituate the sad video clips displayed a novelty response or dishabituated to the happy expressions. These findings suggest that 3-month-old infants of depressed mothers discriminate sad from happy expressions, however, they do not appear to perceive sad expressions as novel.     

Newborns of depressed mothers who received moderate versus light pressure massage during pregnancy

Sixty-four neonates (M age=6.8 days) of depressed mothers who received moderate pressure massage versus light pressure massage therapy during pregnancy (month 5 through month 8) were compared on their behaviors during 15-min observations and on their performance on the Brazelton Neonatal Behavior Assessment Scale. The group of neonates whose mothers received moderate pressure massage spent a greater percent of the observation time smiling and vocalizing, and they received better scores on the orientation, motor, excitability, and depression clusters of the Brazelton scale.     

Greater arousal and less attentiveness to face/voice stimuli by neonates of depressed mothers on the Brazelton Neonatal Behavioral Assessment Scale

Neonates born to depressed (n = 44) versus non-depressed (n = 43) mothers were compared on individual items of the Brazelton Neonatal Behavioral Assessment Scale (NBAS). The neonates of depressed mothers received lower scores on orienting to the live face/voice stimulus and on the alertness items, suggesting they were less attentive. They also scored less optimally on the cuddliness and hand-to-mouth activity items, suggesting they were more aroused. These data lend support to the model that infants of depressed mothers are more aroused and less attentive.     

Prenatal paternal depression

Prenatal depressive symptoms, anxiety, anger and daily hassles were investigated in 156 depressed and non-depressed pregnant women and their depressed and non-depressed partners (fathers-to-be). Depressed versus non-depressed fathers had higher depression, anxiety and daily hassles scores. Although the pregnant women in general had lower anxiety, anger and daily hassles scores than the men, the scores on the measures for depressed fathers and depressed mothers did not differ. Paternal depression appeared to have less effect than maternal depression on their partners’ scores. However, the similarity between the scores of depressed mothers and depressed fathers highlights the importance of screening for depression in fathers-to-be as well as mothers-to-be during pregnancy.     

Recency-to-primacy shift in cue competition

Three experiments were conducted using a lick-suppression preparation with rats to determine whether temporal and physical context shifts modulate the effectiveness of 2 sequentially trained blocking stimuli. Experiment 1 ascertained that it is possible to obtain blocking by conditioning rats to react to a target cue using 2 different blocking cues, each trained with a single-phase blocking paradigm. Experiment 2 showed that the more recently trained blocking stimulus was more effective (i.e., showed a recency effect) when testing was conducted immediately after training, but a long retention interval attenuated blocking by the most recently trained blocking stimulus and increased blocking by the initially trained blocking stimulus (i.e., a recency-to-primacy shift). This shift from recency to primacy affected in Experiment 2 by varying the retention interval was replicated in Experiment 3 by changing the physical context between training and testing. Taken together, the results indicate that the effectiveness of sequentially trained competing stimuli follows the same recency-to-primacy shift rule that is seen in traditional interference phenomena.