An infrared system for the detection of a pigeon''s pecks at alphanumeric characters on a TV screen: the dependency of letter detection on the predictability of one letter by another.

Three pigeons pecked at letters of the alphabet and at the symbol "?" displayed on a computer-driven cathode ray screen. A 4 by 4 matrix of infrared emitting and detecting diodes and associated circuitry identified the location of a pigeon''s responses to the screen. Responses at the target letter T were probabilistically reinforced with food whenever T appeared in a string of three letters in the middle of the screen. Responses at the symbol "?" appearing below this string were probabilistically reinforced whenever T did not appear. The letter F anywhere in the three-character string either strongly predicted the occurrence of the target letter T, in two conditions, or predicted its nonoccurrence, in a third. This manipulation of the frequency with which the familiar letter F predicted T was shown to change the function relating probability of a correct peck at the symbol "?" to the number of Fs in the string. This effect may be interpreted as an instance of the phenomenon where an organism''s acquired knowledge changes what it sees.     

Ethics education in science and engineering: The case of animal research

Conclusion The past one hundred fifty years of debate over the use of animals in research and testing has been characterized mainly byad hominem attacks and on uncritical rejection of the other sides’ arguments. In the classroom, it is important to avoid repeating exercises in public relations and to demand sound scholarship. This paper is a modification of material originally included in the handbook which accompanied the American Association for the Advancement of Science (AAAS) Seminar “Teaching Ethics in Science and Engineering”, 10–11 February 1993.     

Testing complex animal cognition: Concept learning,proactive interference,and list memory

This article describes an approach for assessing and comparing complex cognition in rhesus monkeys and pigeons by training them in a sequence of synergistic tasks, each yielding a whole function for enhanced comparisons. These species were trained in similar same/different tasks with expanding training sets (8, 16, 32, 64, 128 … 1024 pictures) followed by novel‐stimulus transfer eventually resulting in full abstract‐concept learning. Concept‐learning functions revealed better rhesus transfer throughout and full concept learning at the 128 set, versus pigeons at the 256 set. They were then tested in delayed same/different tasks for proactive interference by inserting occasional tests within trial‐unique sessions where the test stimulus matched a previous sample stimulus (1, 2, 4, 8, 16 trials prior). Proactive‐interference functions revealed time‐based interference for pigeons (1, 10 s delays), but event‐based interference for rhesus (no effect of 1, 10, 20 s delays). They were then tested in list‐memory tasks by expanding the sample to four samples in trial‐unique sessions (minimizing proactive interference). The four‐item, list‐memory functions revealed strong recency memory at short delays, gradually changing to strong primacy memory at long delays over 30 s for rhesus, and 10 s for pigeons. Other species comparisons and future directions are discussed.     

Human rights without human supremacism*

Early defenders of the Universal Declaration of Human Rights invoked species hierarchy: human beings are owed rights because of our discontinuity with and superiority to animals. Subsequent defenders avoided species supremacism, appealing instead to conditions of embodied subjectivity and corporeal vulnerability we share with animals. In the past decade, however, supremacism has returned in work of the new ‘dignitarians’ who argue that human rights are grounded in dignity, and that human dignity requires according humans a higher status than animals. Against the dignitarians, I argue that defending human rights on the backs of animals is philosophically suspect and politically self-defeating.     

Human and Animal Subjects of Research: The Moral Significance of Respect versus Welfare

Human beings with diminished decision-making capacities are usually thought to require greater protections from the potential harms of research than fully autonomous persons. Animal subjects of research receive lesser protections than any human beings regardless of decision-making capacity. Paradoxically, however, it is precisely animals’ lack of some characteristic human capacities that is commonly invoked to justify using them for human purposes. In other words, for humans lesser capacities correspond to greater protections but for animals the opposite is true. Without explicit justification, it is not clear why or whether this should be the case. Ethics regulations guiding human subject research include principles such as respect for persons—and related duties—that are required as a matter of justice while regulations guiding animal subject research attend only to highly circumscribed considerations of welfare. Further, the regulations guiding research on animals discount any consideration of animal welfare relative to comparable human welfare. This paper explores two of the most promising justifications for these differences␣between the two sets of regulations. The first potential justification points to lesser moral status for animals on the basis of their lesser capacities. The second potential justification relies on a claim about the permissibility of moral partiality as␣found in common morality. While neither potential justification is sufficient to justify the regulatory difference as it stands, there is possible common ground between supporters of some regulatory difference and those rejecting the current difference.     

Disgust sensitivity and fear of animals: Effect of exposure to violent or revulsive material

Subjects were asked to rate their fear of four categories of animals both before and after viewing one of three brief video films. Subjects watched either (a) a video depicting extreme violence, (b) a video depicting revulsive scenes from a hospital operation, or (c) a video showing neutral landscape scenes. The results suggested that exposure to violent material produced an increase in fear ratings for animals in the Hi Fear/Hi Predatory category (e.g., lion, tiger, shark) which was significantly different from a decrease in fear ratings recorded for all other categories of animals. However, exposure to revulsive material produced an increase in fear ratings to animals in both the Hi Fear/Lo Predatory category (e.g., rat, spider, snake) and the Hi Revulsion category (e.g., slug, maggot, snail) which was significantly different to the decrease in fear ratings recorded for animals in the remaining categories. The neutral landscape scenes produced a decrease in mean fear ratings for all categories of animals. These results are considered further support for a disease-avoidance model of common animal fears, and suggest a causal link between disgust sensitivity and fear of certain fear-relevant animals.     

Characteristics of individuals with fear of spiders

Abstract

This paper reports the results of two studies which investigated some of the factors that differentiated individuals with fear of spiders from those without such fears. The main results suggested that (a) there was little evidence that fear of spiders in nonclinical subjects is normally acquired through direct conditioning experiences; (b) there was some evidence for a familial component to spider fears; (c) there was no support for the view that individuals reporting a fear of spiders were especially sensitized to the movement cues possessed by spiders; (d) fear of spiders was not associated either with higher levels of trait anxiety or with an increased predisposition to other fears in general; but (e) fear of spiders did appear to be associated with increased fear of other animals, but only animals that are normally considered fear-evoking or disgust-evoking. These results provide little support for a traditional conditioning view of spider fears, and they are not entirely consistent with some preparedness accounts of the acquisition of specific fears. However, the results do suggest that fear of spiders is part of a functionally integrated set of animal fears, and it is argued that the present results could be better understood by attempting to integrate predator-defence and disease-avoidance models of animal fears.