Selective association learning in the rat: Generality of response system

Three experiments with rats examined the possibility that the cue-consequence specificity effect is not mediated by the conditioning of selective associations, but instead reflects the selective behavioral expression of taste-illness and exteroceptive-shock conditioning. Experiment 1 showed that the selective aversion performance could be obtained despite the use of locomotor withdrawal from the CS as the index of conditioning. Experiment 2 compared the response profiles of animals conditioned with footshock or illness to presentation of a saccharin or noise CS. During the test with the noise CS, lithium-conditioned subjects did not differ from control rats on any of several behavioral categories, but shock-conditioned rats showed high levels of freezing in response to the noise cue. During the saccharin test, lithium-treated rats engaged in behaviors such as chin wiping, head shaking, and gaping; these behaviors were rarely or never seen in shock-conditioned rats or controls, whose behavioral profiles during the saccharin test were almost identical. Experiment 3, using a blocking design, found that a noise-lithium pairing did not attenuate subsequent conditioning of a saline-lithium association, nor did a saccharin-shock pairing interfere with conditioning of a noise-shock association. These results confirm that the cue-consequence specificity effect is mediated by the selective associability of taste with illness and of exteroceptive cues with footshock.     

Message of Pope Francis to the 11th Assembly of the World Council of Churches

This is the text of the message of greetings of His Holiness Pope Francis to the 11th Assembly of the World Council of Churches, meeting in Karlsruhe, Germany, from 21 August to 8 September 2022.     

Examining civic engagement in ethnic minority youth populations: A literature review and concept analysis

Racial reckoning is defined as the subjugation of Black, Indigenous, and people of Color (BIPOC) to racial hierarchies and subordinate groups that influence multiple well-being outcomes throughout the developmental lifespan and across generations. With the two pandemics of racial reckoning and COVID-19 amidst a growing controversial political landscape, topics around civic engagement have been brought to the forefront of community conversation. Discussions surrounding civic engagement must go beyond addressing issues of public concern and examine the vehicle in which civic engagement may be delivered. This is becoming increasingly important as civic engagement is one of the main avenues of social change through individual and collective action, particularly regarding racial reckoning and healthcare disparities highlighted by COVID-19. The paper focuses on civic engagement among ethnic minority youth and young adults. An integrated model of civic engagement was created based off what was learned through this review. This proposed model of civic engagement is meant to be the first step to addressing the gap in civic engagement literature for ethnic minority youth. Weaknesses and future considerations regarding the model will also be discussed, as well as any implications for ethnic minority youth and young adults.     

Lifespan normative data (18–89 years) for Raven's Advanced Progressive Matrices Set I

Raven's Advanced Progressive Matrices (APM) Set I is a validated and brief test of fluid intelligence, ideal for use in busy clinical settings. However, there is a dearth of normative data allowing an accurate interpretation of APM scores. To address this, we present normative data from across the adult lifespan (18–89 years) for the APM Set I. Data are presented in five age cohorts (total N = 352), including two older adult cohorts (65–79 years and 80–89 years), which allows age-standardized assessment. We also present data from a validated measure of premorbid intellectual ability, which was absent from previous standardizations of longer forms of the APM. In line with previous findings, a striking age-related decline was noted, beginning relatively early in adulthood and most marked amongst lower-scoring individuals. Older adults did not demonstrate difficulty with specific test items or make an increased proportion of specific errors. Sex was not a significant predictor of performance. The data set is of particular use in the neuropsychological assessment of older adults, given the known susceptibility of fluid intelligence to both the effects of normal ageing and acquired brain injury in older age. The results are discussed in light of theories of neurological ageing.     

Pain in the eye of the beholder: Variations in pain visual representations as a function of face ethnicity and culture

Pain experienced by Black individuals is systematically underestimated, and recent studies have shown that part of this bias is rooted in perceptual factors. We used Reverse Correlation to estimate visual representations of the pain expression in Black and White faces, in participants originating from both Western and African countries. Groups of raters were then asked to evaluate the presence of pain and other emotions in these representations. A second group of White raters then evaluated those same representations placed over a neutral background face (50% White; 50% Black). Image-based analyses show significant effects of culture and face ethnicity, but no interaction between the two factors. Western representations were more likely to be judged as expressing pain than African representations. For both cultural groups, raters also perceived more pain in White face representations than in Black face representations. However, when changing the background stimulus to the neutral background face, this effect of face ethnic profile disappeared. Overall, these results suggest that individuals have different expectations of how pain is expressed by Black and White individuals, and that cultural factors may explain a part of this phenomenon     

Aggression as a reinforcer: operant behavior in the mouse-killing rat

Two experiments examined mouse killing as a reinforcer of key pressing by rats that killed mice. In Experiment I, mouse-killing rats performed the key-pressing response when each press was reinforced with presentation of a mouse. Offered a choice between a key that yielded presentation of mice and one that did not, the rats preferred the key that yielded mice. When the contingency was reversed, the rats preferred the other key and continued to kill mice. In Experiment II, mouse-killing rats that did not kill rat pups performed a key-pressing response reinforced with presentation of mice on a variable-interval schedule. In tests for responding reinforced on that schedule with presentation of normal mice, anesthetized mice, dead mice, or rat pups, these rats that killed mice but not rat pups exhibited a decline in response rate when rat pups were the reinforcer. Altering the condition of the mice did not significantly affect performance.     

The development of stimulus control with and without a lighted key

In two experiments, the effect of an illuminated response key on the acquisition of stimulus control by an airflow stimulus was assessed. In the first experiment, pigeons were given nondifferential training with airflow emerging from behind the response key in one of three conditions of illumination: trained to peck a lighted key, trained to peck an unlighted key with a houselight present, trained to peck a key in total darkness. After 10 days of training on a variable-interval schedule of reinforcement, all subjects were given a generalization test on airflow velocity. The gradients for subjects trained in the dark were sharp, while those for subjects trained in lighted conditions were shallow. In the second experiment, the effect of an irrelevant keylight on the acquisition of an airflow velocity discrimination was assessed. Two groups of pigeons were trained to discriminate two airflow velocities. One group was trained with a lighted response key and the other was trained to peck the response key in total darkness. The dark-trained subjects acquired the discrimination more rapidly. The results demonstrate that the acquisition of stimulus control by airflow with either a differential or nondifferential training procedure can be overshadowed by keylight.     

Effects of deprivation upon counting and timing in rats

Two procedures were used in an investigation of the effects of deprivation upon counting and timing. Under the first procedure, fixed minimum interval (FMI), the rat received liquid reinforcement every time it pressed bar B after having waited a minimum of 5 sec following a press on bar A. Under the second procedure, fixed consecutive number (FCN), reinforcement was delivered every time the rat pressed bar B following a run of at least four consecutive responses on bar A.

Water deprivation was varied over a set of values ranging from 4 to 56 hr. Deprivation had almost no effect on the waiting time in the FMI procedure, or on the number of responses per run in the FCN procedure. With both procedures, increasing deprivation shortened the pause between reinforcement and the next response. In the FCN procedure, the speed with which the runs were executed increased with increasing deprivation, although the number of responses in these runs was relatively unaffected.