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Associative learning plays a fundamental role in the life of honey bees, especially in the context of foraging for food sources. This learning capacity can be investigated through controlled experiments conducted under laboratory, semi-natural, and near-natural conditions, to understand the general principles of learning and motivation. Honey bees can be trained to solve different elemental and non-elemental learning tasks by pairing a conditioned stimulus such as an odor with sucrose as an unconditioned stimulus and reward. Laboratory studies with restrained bees demonstrated that sucrose responsiveness is positively correlated with both elemental olfactory learning performance and responsiveness to stimuli of different sensory modalities, such as odors and visual stimuli. Here, we tested for the first time how responsiveness to sucrose and light is related to performance in elemental and non-elemental visual learning under free-flying conditions. Sensory responsiveness and learning proficiency did not correlate, nor did sucrose responsiveness correlate with responsiveness to light. These results indicate that relationships among responsiveness to sucrose and light and learning proficiency, as established under restrained laboratory conditions, may not translate to the natural behavior of bees in the field. This finding points toward the context-dependent importance of responsiveness to light and sucrose during associative learning under restrained or free-flying conditions.

Configural learning is a form of associative learning in which the conditioned stimulus is an overall complex of stimulus elements rather than individual stimuli or their isolated properties. Overall analysis of the entire configuration as a whole is required for successful solution of the challenges of this type of associative learning. The ability to analyze not only the individual physical aspects of a stimulus or the individual objects of a visual scene, but also their overall combination, provides significant evolutionary advantages, as configurations often have significantly greater predictive power than the individual elements or features of a stimulus. Furthermore, the ability to analyze integrated combinations of elements or features of a stimulus field can be seen as an initial primitive manifestation of consciousness. This review considers the history of the development of the concept of configural learning, the main methodological research approaches, and currently available neurophysiological data on the putative neuronal basis of this phenomenon. The most interesting studies appear to be those addressing configural learning processes in humans using modern neuroimaging methods, as these provide an opportunity to gain insight into the operation of the whole brain. In conclusion, this review determines which problems in existing research need to be overcome in the future to provide a more complete understanding of the neurophysiology of the phenomenon of configural learning.

Spatial learning and memory have been studied for several decades. Analyses of these processes pose fundamental scientific questions but are also relevant from a biomedical perspective. The cellular, synaptic and molecular mechanisms underlying spatial learning have been intensively investigated, yet the behavioral mechanisms/strategies in a spatial task still pose unanswered questions. Spatial learning relies upon configural information about cues in the environment. However, each of these cues can also independently form part of an elemental association with the specific spatial position, and thus spatial tasks may be solved using elemental (single CS and US association) learning. Here, we first briefly review what we know about configural learning from studies with rodents. Subsequently, we discuss the pros and cons of employing a relatively novel laboratory organism, the zebrafish in such studies, providing some examples of methods with which both elemental and configural learning may be explored with this species. Last, we speculate about future research directions focusing on how zebrafish may advance our knowledge. We argue that zebrafish strikes a reasonable compromise between system complexity and practical simplicity and that adding this species to the studies with laboratory rodents will allow us to gain a better understanding of both the evolution of and the mechanisms underlying spatial learning. We conclude that zebrafish research will enhance the translational relevance of our findings.

Fluoride occurs naturally in the terrestrial and aquatic environment and is a major component in tea. Prolonged fluoride exposure alters metabolic activity in several aquatic invertebrates. For the first time, we investigated the effects of fluoride on cognition in the pond snail Lymnaea stagnalis as it is capable of a higher form of associative learning called configural learning. We first showed suppressive effects of black tea and fluoride on feeding (i.e., rasping) behavior. We then investigated how fluoride may alter cognition by introducing fluoride (1.86 mg/L) before, during, after, a day before and a week before the snails underwent the configural learning training procedure. Our results show that any 45-min exposure to fluoride (before, during or after a configural learning training procedure) blocks configural learning memory formation in Lymnaea and these effects are long-lasting. One week after a fluoride exposure, snails are still unable to form a configural learning memory and this result is upheld when the snails are exposed to a lower concentration of fluoride, one which is naturally occurring in ponds that a wild strain of Lymnaea can be found (0.3 mg/L). Thus, fluoride obstructs configural learning memory formation in a fluoride-naïve, inbred strain of Lymnaea.

The ability to orient is critical for mobile species. Two visual cues, geometry (e.g., distance and direction) and features (e.g., colour and texture) are often used when establishing one’s orientation. Previous research has shown the use of these cues, in particular, geometry, may decline with healthy aging. Few studies have examined whether degenerative aging processes show similar time points for the decline of geometry use. The present study examined this issue by training adult and aged mice from two strains, a healthy wild-type and an Alzheimer’s model, to search for a hidden platform in a rectangular water maze. The shape of the maze provided geometric information, and distinctive features were displayed on the walls. Following training, manipulations to the features were made to examine whether the mice were able to use the features and geometry, and whether they showed a preference between these two cue types. Results showed that although Alzheimer’s transgenic mice were slower to learn the task, overall age rather than strain, was associated with a degradation in use of geometry. However, the presence of seemingly uninformative features (due to their redundancy) facilitated the use of geometry. Additionally, when features and geometry provided conflicting information, only young wild-type mice showed a primary use of features. Our results suggest the failure to use geometry may be a generalized function of aging, and not a diagnostic feature of degeneration for mice. Whether this is also the case for other mammals, such as humans for which the mouse is an important medical model, remains to be examined.

In two experiments, rats were given intermixed or blocked preexposure to two similar compound stimuli, AX and BX. Following preexposure, conditioning trials took place in which AX (Experiment 1 ) or a novel compound stimulus NX (Experiment 2 ) was paired with a food-unconditioned stimulus in an appetitive Pavlovian preparation. Animals that were given alternated preexposure showed lower generalization from AX to BX (Experiment 1 ) and from NX to a new compound, ZX (Experiment 2 ), than animals that were given blocked preexposure, a perceptual learning and a perceptual learning transfer effect, respectively.

This article introduces a new “real-time” model of classical conditioning that combines attentional, associative, and \"flexible\" configural mechanisms. In the model, attention to both conditioned (CS) and configural (CN) stimuli are modulated by the novelty detected in the environment. Novelty increases with the unpredicted presence or absence of any CS, unconditioned stimulus (US), or context. Attention regulates the magnitude of the associations CSs and CNs form with other CSs and the US. We incorporate a flexible configural mechanism in which attention to the CN stimuli increases only after the model has unsuccessfully attempted learn input-output combinations with CS–US associations. That is, CSs become associated with the US and other CSs on fewer trials than they do CNs. Because the CSs activate the CNs through unmodifiable connections, a CS can become directly and indirectly (through the CN) associated with the US or other CSs. In order to simulate timing processes, we simply assume that a CS is formed by a temporal spectrum of short-duration CSs that are activated by the nominal CS trace. The model accurately describes 94 % of the basic properties of classical conditioning, using fixed model parameters and simulation values in all simulations.

Two experiments investigated the capacity of rats to learn configural discriminations requiring integration of contextual (where) with temporal (when) information. In Experiment 1, during morning training sessions, food was delivered in context A and not in context B, whereas during afternoon sessions food was delivered in context B and not in context A. Rats acquired this discrimination over the course of 20 days. Experiment 2 employed a directly analogous aversive conditioning procedure in which footshock served in place of food. This procedure allowed the acquisition of the discrimination to be assessed through changes in activity to the contextual + temporal configurations (i.e., inactivity or freezing) and modulation of the immediate impact of footshock presentations (i.e., post-shock activity bursts). Both measures provided evidence of configural learning over the course of 12 days, with a final test showing that the presentation of footshock resulted in more post-shock activity in the nonreinforced than reinforced configurations. These behavioral effects reveal important parallels between (i) configural discrimination learning involving components allied to episodic memory and (ii) simple conditioning.

Two strategies used to uncover neural systems for episodic-like memory in animals are discussed: (i) an attribute of episodic memory (what? when? where?) is examined in order to reveal the neuronal interactions supporting that component of memory; and (ii) the connections of a structure thought to be central to episodic memory in humans are studied at a level of detail not feasible in humans. By focusing on spatial memory (where?) and the hippocampus, it has proved possible to bring the strategies together. A review of lesion, disconnection and immediate early-gene studies in animals reveals the importance of interactions between the hippocampus and specific nuclei in the diencephalon (most notably the anterior thalamic nuclei) for spatial memory. Other parts of this extended hippocampal system include the mammillary bodies and the posterior cingulate (retrosplenial) cortex. Furthermore, by combining lesion and immediate early-gene studies it is possible to show how the loss of one component structure or tract can influence the remaining regions in this group of structures. The validity of this convergent approach is supported by new findings showing that the same set of regions is implicated in anterograde amnesia in humans.

The present study explored the contextual control of running-based taste aversion in rats by giving rats a salty solution in Context A followed by wheel running and the same solution in Context B without running. Experiment 1 demonstrated that the contextual control of saline aversion was greater for Sprague-Dawley (SD) rats than for Wistar rats, and that the superior performance of the SD rats was maintained even after a 16-day break. Experiment 2 replicated the contextual control in a new set of SD rats, with the same type of bottles/spouts employed in both contexts. Experiment 2 also revealed three features of this context discrimination learning: (a) failure to show conditional control in a two-bottle (saline vs. water) choice test, (b) transfer to tap water intake, and (c) maintenance of good performance after exposure to those contexts without the conditioned taste solution. The theoretical implications of these features are discussed.