Conditional same/different concept learning in the short-beaked echidna (Tachyglossus aculeatus)

Generalized, cross-modal, and incrementing non-matching-to-sample in rats

Same/different concept learning has been demonstrated in previous research in rats using matching- and non-matching-to-sample procedures with olfactory stimuli. In Experiment 1, rats were trained on the non-matching-to-sample procedure with either three-dimensional (3D plastic objects; n = 3) or olfactory (household spices, n = 5) stimuli, then tested for transfer to novel stimuli of the same, and then the alternate, modality. While all three rats trained with olfactory stimuli showed generalized non-matching to novel odors, only one rat learned the 3D relation and showed generalized transfer to novel objects. Importantly, in this rat the 3D non-matching relation then immediately transferred to odors. In contrast, rats trained with scents did not show transfer to novel 3D stimuli until after training with one or two 3D stimulus sets. In Experiment 2, four rats were trained on an incrementing non-matching-to-sample task featuring 3D plastic objects as stimuli (3D Span Task). Responses to session-novel stimuli resulted in reinforcement. Only two rats learned the 3D Span Task; one rat performed with high accuracy even with up to 17 session-novel objects in a session. While these findings emphasize the exceptional olfactory discrimination of rats relative to that with 3D/tactile/visual cues, they also show that relational learning can be demonstrated in another modality in this species. Further, the present study provides some evidence of cross-modal transfer of relational responding in rats.

Exploring Higher-Order Conceptual Learning in an Arthropod with a Large Multisensory Processing Center

Simple Summary

It is difficult to measure animal intelligence because the definition of ‘intelligence’ varies, and many animals are good at specific tasks used to measure intelligence or cognition. To address this, scientists often look for evidence of common cognitive abilities. One such ability, the ability to learn concepts, is thought to be rare in animals, especially invertebrates. Concepts include the ideas of ‘same’ and ‘different’. These concepts can be applied to anything in the environment while also being independent of those objects and can help animals understand and survive their environment. Amblypygids, a relative of spiders, live in tropical and subtropical areas, are very good learners, and have a large, complex brain region known to process information from multiple senses. We tested whether amblypygids could learn the concept of ‘same’ by training them to move toward a stimulus that matched with an initial stimulus. We also trained some individuals to learn the concept ‘different’ by training them to move toward a non-matching stimulus. When we used new stimuli, the amblypygids did not move toward the correct stimulus significantly more often than the incorrect stimulus, suggesting either they are unable to learn these higher-order concepts or our experimental design failed to elicit that ability.

Abstract

Comparative cognition aims to understand the evolutionary history and current function of cognitive abilities in a variety of species with diverse natural histories. One characteristic often attributed to higher cognitive abilities is higher-order conceptual learning, such as the ability to learn concepts independent of stimuli—e.g., ‘same’ or ‘different’. Conceptual learning has been documented in honeybees and a number of vertebrates. Amblypygids, nocturnal enigmatic arachnids, are good candidates for higher-order learning because they are excellent associational learners, exceptional navigators, and they have large, highly folded mushroom bodies, which are brain regions known to be involved in learning and memory in insects. In Experiment 1, we investigate if the amblypygid Phrynus marginimaculatus can learn the concept of same with a delayed odor matching task. In Experiment 2, we test if Paraphrynus laevifrons can learn same/different with delayed tactile matching and nonmatching tasks before testing if they can transfer this learning to a novel cross-modal odor stimulus. Our data provide no evidence of conceptual learning in amblypygids, but more solid conclusions will require the use of alternative experimental designs to ensure our negative results are not simply a consequence of the designs we employed.

Tachyglossus aculeatus (Monotremata: Tachyglossidae)

Tachyglossus aculeatus (Shaw, 1792) is a monotreme commonly called the short-beaked echidna. Although considered Australia’s most common native mammal because of its continent-wide distribution, its population numbers everywhere are low. It is easily distinguished from all other native Australian mammals because of its spine-covered body, hairless beak, and unique “rolling” gait. The five subspecies, one of which is found in Papua New Guinea, show variations in fur density, spine diameter, length, and number of grooming claws. The Kangaroo Island short-beaked echidna Tachyglossus aculeatus multiaculeatus is listed as “Endangered” but all other Tachyglossus are listed as “Least Concern” in the 2016 International Union for Conservation of Nature and Natural Resources Red List.

Effects of set size on identity and oddity abstract-concept learning in rats

Match (MTS) and non-match-to-sample (NMTS) procedures are used to assess concepts of identity and oddity across species and are measured by transfer performance to novel stimuli. The number of exemplars used in training (set size) has been shown to affect learning with evidence of larger set sizes promoting concept learning in several species. The present study explored the effects of set size and procedure on concept learning in rats using olfactory stimuli. Concept learning was assessed for 20 rats via transfer tests consisting of novel stimuli after rats were initially trained to either MTS or NMTS with two or ten stimuli as exemplars. No difference was found in acquisition or transfer between MTS and NMTS, but rats trained with ten stimuli performed better on novel transfer tests than rats trained with two. When set size was expanded for rats originally trained with two stimuli and rats were re-tested with ten novel stimuli, performance showed full transfer demonstrating that training with multiple exemplars facilitates concept learning.

Translating Behavior Analysis: a Spectrum Rather than a Road Map

Much has been written about the potential benefits of translational research in behavior analysis, but a lack of consensus about what constitutes "translational" creates a barrier to effective knowledge-practice innovation within the discipline and across other sciences. We propose a tiered system, adapted from a biomedical translational pathway, for classifying behavior analysis research on a basic-applied spectrum. Tier 0 is blue sky basic science in which the subjects, behaviors, stimuli, and settings are selected for convenience. Tier 1 is use-inspired basic science with a socially important end game and research subject. Tier 2 is solution-oriented research that attempts to solve a specific problem in a socially important subject, but 1 or more aspects of the research are selected for purposes of experimental control rather than social importance. Tier 3 is applied behavior analysis research that studies a problem of social significance for the subject and involves behaviors, stimuli, and settings that are socially important. Tier 4 is impact assessment in which behavioral technology is applied with a direct benefit to society. We provide examples of behavior-analytic research in each tier and evaluate the potential benefits of organizing behavior analysis in this way.

Same or different? Abstract relational concept use in juvenile bamboo sharks and Malawi cichlids

Sorting objects and events into categories and concepts is an important cognitive prerequisite that spares an individual the learning of every object or situation encountered in its daily life. Accordingly, specific items are classified in general groups that allow fast responses to novel situations. The present study assessed whether bamboo sharks Chiloscyllium griseum and Malawi cichlids Pseudotropheus zebra can distinguish sets of stimuli (each stimulus consisting of two abstract, geometric objects) that meet two conceptual preconditions, i.e., (1) “sameness” versus “difference” and (2) a certain spatial arrangement of both objects. In two alternative forced choice experiments, individuals were first trained to choose two different, vertically arranged objects from two different but horizontally arranged ones. Pair discriminations were followed by extensive transfer test experiments. Transfer tests using stimuli consisting of (a) black and gray circles and (b) squares with novel geometric patterns provided conflicting information with respect to the learnt rule “choose two different, vertically arranged objects”, thereby investigating (1) the individuals’ ability to transfer previously gained knowledge to novel stimuli and (2) the abstract relational concept(s) or rule(s) applied to categorize these novel objects. Present results suggest that the level of processing and usage of both abstract concepts differed considerably between bamboo sharks and Malawi cichlids. Bamboo sharks seemed to combine both concepts—although not with equal but hierarchical prominence—pointing to advanced cognitive capabilities. Conversely, Malawi cichlids had difficulties in discriminating between symbols and failed to apply the acquired training knowledge on new sets of geometric and, in particular, gray-level transfer stimuli.

Successive odor matching- and non-matching-to-sample in rats: A reversal design

There is a growing body of research on matching- and non-matching-to-sample (MTS, NMTS) relations with rats using olfactory stimuli; however, the specific characteristics of this relational control are unclear. In the current study we examine MTS and NMTS in rats with an automated olfactometer using a successive (go, no-go) procedure. Ten rats were trained to either match- or non-match-to-sample with common scents (apple, cinnamon, etc.) as olfactory stimuli. After matching or non-matching training with four odorants, rats were tested for transfer twice with four new odorants on each test. Most rats trained on MTS showed immediate transfer to new stimuli, and most rats trained on NMTS showed full transfer by the second set of new odors. After meeting criterion on the second transfer test, the contingencies were reversed with four new odor stimuli such that subjects trained on matching were shifted to non-matching and vice versa. Following these reversed contingencies, the effects of the original training persisted for many trials with new odorants. These data extend previous studies on same-different concept formation in rats, showing strong generalization requiring few exemplars. The critical role of olfactory stimuli is discussed.