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En 1996, le Conseil national des programmes, sous la présidence de Luc Ferry, se propose de mettre en œuvre la proposition 51 du Nouveau contrat pour l’école : publier un manuel de référence qui soit une mise en œuvre du socle commun de connaissances. L’article montre que cette volonté se heurte à de nombreuses difficultés : à qui ce manuel est-il destiné ? Qui va le rédiger ? S’agit-il d’un manuel ou d’un rapport ? Celui-ci fixerait ainsi les lignes directrices permettant de rédiger un manuel du socle commun des connaissances. Des projets ont été rédigés pour un manuel en deux volumes, l’un consacré aux sciences, l’autre aux humanités. En définitive, ce manuel ne vit pas le jour. Pour autant, le travail n’a pas été vain puisqu’au projet initial a été substitué la réalisation d’un cahier d’exigences à destination des collégiens. C’est en quelque sorte la première mise en œuvre du socle commun.

The increasing use of mice models in cognitive tasks that were originally designed for rats raises crucial questions about cross‐species comparison in the study of spatial cognition. The present review focuses on the major neuroethological differences existing between mice and rats, with particular attention given to the neurophysiological basis of space coding. While little difference is found in the basic properties of space representation in these two species, it appears that the stability of this representation changes more drastically over time in mice than in rats. We consider several hypotheses dealing with attentional, perceptual, and genetic aspects and offer some directions for future research that might help in deciphering hippocampal function in learning and memory processes. WIREs Cogn Sci2016, 7:406‐421. doi: 10.1002/wcs.1411 For further resources related to this article, please visit the WIREs website.

Considerable evidence has shown a clear dissociation between the dorsomedial (DMS) and the dorsolateral (DLS) striatum in instrumental conditioning. In particular, DMS activity is necessary to form action-outcome associations, whereas the DLS is required for developing habitual behavior. However, few studies have investigated whether a similar dissociation exists in more complex goal-directed learning processes. The present study examined the role of the two structures in such complex learning by analyzing the effects of excitotoxic DMS and DLS lesions during the acquisition and extinction of spatial alternation behavior, in a continuous alternation T-maze task. We demonstrate that DMS and DLS lesions have opposite effects, the former impairing and the latter improving animal performance during learning and extinction. DMS lesions may impair the acquisition of spatial alternation behavior by disrupting the signal necessary to link a goal with a specific spatial sequence. In contrast, DLS lesions may accelerate goal-driven strategies by minimizing the influence of external stimuli on the response, thus increasing the impact of action-reward contingencies. Taken together, these results suggest that DMS- and DLS-mediated learning strategies develop in parallel and compete for the control of the behavioral response early in learning.

Les travaux sur les bases neurales de la mémoire spatiale suggèrent l’existence d’un réseau neuronal étendu dédié au codage de l’information spatiale et permettant l’orientation de l’organisme dans l’espace. Ce réseau inclut les cellules de lieu de l’hippocampe, les cellules d’orientation de la tête que l’on trouve dans différentes régions dont le post-subiculum, et les cellules grilles du cortex entorhinal. Certaines caractéristiques de l’activité des cellules de lieu ont été récemment mises en évidence et éclairent la contribution de l’hippocampe à la construction de la mémoire. Par exemple, la mémorisation d’un nouvel environnement repose sur un code de population dynamique dans lequel l’activité des neurones hippocampiques change brutalement pour adopter des états stables façonnés pendant l’apprentissage. Nous présentons ici une brève revue de certaines de ces propriétés émergentes pour montrer comment elles contraignent le code hippocampique de la mémoire.

The rat hippocampus contains place cells whose firing is location‐specific. Although many properties of place cells have been uncovered, little is known about their actual contribution to the animal's spatial performance. In this study, we addressed this issue by recording place cells while rats solved a continuous spatial alternation task in which they had to alternate between the two arms of a Y‐maze to get a food reward in the third (goal) arm. By manipulating the information available to the animals, we induced the cells to establish their fields in locations that were out of register relative to their standard position, thus making them inconsistent with the learned spatial task. When this happened, the rats' performance in the alternation task was markedly decreased. In addition, the nature of the behavioral errors during inconsistent field placements also changed dramatically in a way that was highly indicative of the rats' spatial disorientation. These results suggest that there is a functional relationship between the spatial firing patterns of place cells and the spatial behavior of the rat, thus strengthening the idea that these cells are part of a navigational system. Hippocampus 2001;11:377–390. © 2001 Wiley‐Liss, Inc.

Hippocampal place cells in rats display spatially selective firing in relation to both external and internal cues. In the present study, we assessed the effects of removing visual and/or olfactory cues on place field stability. Place cell activity was recorded as rats searched for randomly scattered food in a cylinder. During an initial recording session, the lights were on and the only available cue was a single white cue card. Following this session, three sessions were run in a row with the cue card removed. In addition, the lights were either turned off or left on and the floor was either cleaned or left unchanged, thus creating four conditions: dark/cleaning, dark/no cleaning, light/cleaning, and light/no cleaning. A fifth session was run with the cue card back on the cylinder wall and the lights turned on. The rat remained in the cylinder during all sessions without being removed at any time. In the dark/cleaning and light/cleaning conditions, most place fields were not stable (i.e., abruptly shifted position). In addition, half of the cells stopped firing in the dark/cleaning condition. In contrast, in the dark/no cleaning and light/no cleaning conditions, most place fields remained stable across sessions. These results suggest that 1) rats are not able to rely on only movement-related information to maintain a stable place representation, 2) visual input is necessary for the firing of a large number of cells, and 3) olfactory information can be used to compensate for the lack of visuospatial information. Hippocampus 2000;10:64–76. © 2000 Wiley-Liss, Inc.

Growing evidence suggests that the associative parietal cortex (APC) of the rat is involved in the processing of spatial information. This observation raises the issue of the respective functions of the APC and the hippocampus in spatial processing as well as of their possible interactions. In this paper, we review neuroanatomical, electrophysiological, and behavioral data that support the existence of such functional interactions. Our hypothesis is that the APC is involved in the initial combination of visuospatial information and self-motion information necessary for the integration of egocentrically acquired information into allocentrically coded information, the latter step being completed in the hippocampus. The dialogue between the hippocampus and the APC is therefore crucial, particularly when the elaboration and/or updating of an allocentric representation depends on complex combinations of visuospatial and self-motion information. Hippocampus 10:491–499, 2000 © 2000 Wiley-Liss, Inc.

Hippocampal place cells in rats display spatially selective firing in relation to both external and internal cues. In the present study, we assessed the effects of removing visual and/or olfactory cues on place field stability. Place cell activity was recorded as rats searched for randomly scattered food in a cylinder. During an initial recording session, the lights were on and the only available cue was a single white cue card. Following this session, three sessions were run in a row with the cue card removed. In addition, the lights were either turned off or left on and the floor was either cleaned or left unchanged, thus creating four conditions: dark/cleaning, dark/no cleaning, light/cleaning, and light/no cleaning. A fifth session was run with the cue card back on the cylinder wall and the lights turned on. The rat remained in the cylinder during all sessions without being removed at any time. In the dark/cleaning and light/cleaning conditions, most place fields were not stable (i.e., abruptly shifted position). In addition, half of the cells stopped firing in the dark/cleaning condition. In contrast, in the dark/no cleaning and light/no cleaning conditions, most place fields remained stable across sessions. These results suggest that 1) rats are not able to rely on only movement‐related information to maintain a stable place representation, 2) visual input is necessary for the firing of a large number of cells, and 3) olfactory information can be used to compensate for the lack of visuospatial information. Hippocampus 2000;10:64–76. © 2000 Wiley‐Liss, Inc.

Growing evidence suggests that the associative parietal cortex (APC) of the rat is involved in the processing of spatial information. This observation raises the issue of the respective functions of the APC and the hippocampus in spatial processing as well as of their possible interactions. In this paper, we review neuroanatomical, electrophysiological, and behavioral data that support the existence of such functional interactions. Our hypothesis is that the APC is involved in the initial combination of visuospatial information and self‐motion information necessary for the integration of egocentrically acquired information into allocentrically coded information, the latter step being completed in the hippocampus. The dialogue between the hippocampus and the APC is therefore crucial, particularly when the elaboration and/or updating of an allocentric representation depends on complex combinations of visuospatial and self‐motion information. Hippocampus 10:491–499, 2000 © 2000 Wiley‐Liss, Inc.

The angular positions of hippocampal place cell firing fields are accurately controlled by the position of a single salient cue card attached to the wall of a recording cylinder; when the card is rotated, fields rotate equally. In contrast, the control exerted by 3-dimensional objects placed directly in the recording arena depends on their arrangement. When three objects lie on the vertices of an isosceles triangle near the center of the cylinder they rarely exert any control over the angular positions of firing fields. However, if the isosceles triangle is dilated so that its vertices are against the apparatus wall, the objects exert virtually ideal control over angular field position. Why do the objects gain control when they are against the cylinder wall? One possibility is that the asymmetry in the object set is more easily detected when the objects are far apart so that they provide a better polarizing cue. This hypothesis assumes that the identity of individual landmarks is not recognized by the place cell system whereas their geometric arrangement provides crucial information for controlling place field positions. If this is true, putting the 3 objects against the cylinder wall on the vertices of an equilateral triangle should cause a loss of stimulus control over the angular positions of firing fields. To the contrary, we found that the firing fields of most place cells (23/29) were accurately controlled by the equilateral object arrangement. Moreover, 5/6 of the uncontrolled cells were in a single animal. These results bolster our previous suggestion that the centrally placed objects fail to control place field positions because the computations necessary to form a stable reference frame are very difficult when the animal can go between stimuli. Hippocampus 1999;9:432–443. © 1999 Wiley-Liss, Inc.

This experiment investigated the role of exploration in the formation of maps of the environment. The effects of spatial rearrangement of four familiar objects in an open field on subsequent exploratory behavior were studied in hamsters (Mesocricetus auratus). During two exploratory sessions, four groups of subjects were exposed to objects in a particular spatial relation to each other and to a distal pattern. During a testing session, the control group was exposed to the same situation as during the first two sessions, and the three experimental groups were exposed to various object rearrangements. The hamsters in the experimental groups, but not those in the control group, renewed their exploration of the objects during the testing session, as measured by the number of contacts with the objects and the time spent investigating them. Further analyses of the nature of the reinvestigated objects (i.e., displaced or nondisplaced) support the hypothesis that, through exploration, a long-lasting representation of the environment is built up on the basis of the topological relations among the objects, the overall geometric structure provided by the arrangement of the objects, and the relations between the objects and extra-apparatus landmarks.

Two groups of six cats were subjected to a spatial learning task in cross-mazes that differed only in the spatial relationship between the goal and the single available visual cue. When this cue was remote from the goal (“mapping situation”), the cats did not need more testing days to reach the learning criterion than when it was above the goal (“guidance situation”). Additional behavioural data gave evidence of two information-gathering strategies within each group: the first consisted of taking the relevant information from the starting point; the second was to choose the correct path from the central choice-point. These strategies were discussed in the light of O'Keefe and Nadel's theory (1978) concerning two spatial behaviours, mapping and route-following.The results of a second experiment showed that the cats subjected to the mapping situation were markedly less affected than those subjected to the guidance situation by a delay introduced between the moment when the relevant cue was still available and the moment when the subjects were allowed to run to the goal.In a third experiment, it was shown that only cats that were seen as choosing their path from the starting point during learning (Experiment 1) succeeded in using short-cuts: subjects that chose from the central choicepoint needed to pass through this place when a shorter path was available.These results show that the processes involved in spatial behaviours may be characterized by taking into account some of the behavioural components. Furthermore, the properties of these processes can be assessed with additional experiments, such as delayed-reaction tasks and short-cutting tests.

Mammals are able to process the location-based (site-dependent) information provided by the spatial layout of landmarks to return to an inconspicuous place (the goal) whose location has been memorized exocentrically by reference to the landmarks. We have developed an algorithm accounting for this place navigation ability. This algorithm is based on the angular information provided by the bearings and angular sizes of landmarks, rather than on metric distances. It is implemented by a system that combines elementary computing procedures and two types of simple associative memory network. One type of network enables the animal to learn how the environmental perspective changes when it makes a one-step translation in any direction, whereas the other type enables the animal to learn how the current panorama is oriented with respect to an overall reference direction. This system highlights the fundamental role of exploration of the environment prior to place navigation, and assigns specific functions to hippocampal place cells and postsubicular head-direction cells.

4 cats were given path-selection problems, with reference to the property of the correct path to lead to a visible goal. Choices were related first to the direction of the goal, then to the connectedness properties of the path if direction of the goal could not be used as a pertinent cue.

The angular positions of hippocampal place cell firing fields are accurately controlled by the position of a single salient cue card attached to the wall of a recording cylinder; when the card is rotated, fields rotate equally. In contrast, the control exerted by 3‐dimensional objects placed directly in the recording arena depends on their arrangement. When three objects lie on the vertices of an isosceles triangle near the center of the cylinder they rarely exert any control over the angular positions of firing fields. However, if the isosceles triangle is dilated so that its vertices are against the apparatus wall, the objects exert virtually ideal control over angular field position. Why do the objects gain control when they are against the cylinder wall? One possibility is that the asymmetry in the object set is more easily detected when the objects are far apart so that they provide a better polarizing cue. This hypothesis assumes that the identity of individual landmarks is not recognized by the place cell system whereas their geometric arrangement provides crucial information for controlling place field positions. If this is true, putting the 3 objects against the cylinder wall on the vertices of an equilateral triangle should cause a loss of stimulus control over the angular positions of firing fields. To the contrary, we found that the firing fields of most place cells (23/29) were accurately controlled by the equilateral object arrangement. Moreover, 5/6 of the uncontrolled cells were in a single animal. These results bolster our previous suggestion that the centrally placed objects fail to control place field positions because the computations necessary to form a stable reference frame are very difficult when the animal can go between stimuli. Hippocampus 1999;9:432–443. © 1999 Wiley‐Liss, Inc.

Many cells recorded from the dorsal hippocampus of freely moving rats are intensely active only when the rat's head is in a particular part of its environment. For this reason, such units are called 'place cells'. We have investigated whether place cells are also found in the ventral hippocampus. Recordings were made from ventral hippocampal units while rats chased food pellets in a cylindrical arena. The rat's position was simultaneously recorded by tracking a light on the rat's head. Our data show the existence of cells in the ventral hippocampus whose positional firing patterns and electrophysiological properties are very similar to those of dorsal hippocampal place cells.

Previous studies suggest that, in both humans and rats, the prefrontal cortex (PFC) is involved in both selective and divided attention. We have also shown that the PFC is involved in response selection and that its involvement is modulated by the cognitive effort required by the task. However, the role of the PFC is much less clear when no response selection is required. The purpose of the present experiments was to assess the role of the PFC in attentional functions with a low response-selection demand. We used two tasks in which information processing was effortful but where the demand on a response selection process is low. Moreover, we assessed two different types of visual attentional functions: selective attention (Experiment 1) and sustained attention (Experiment 2). The results showed a differential involvement of the PFC in the two tasks. Selective attention was not impaired by prefrontal lesions when the number of possible positions for the stimulus on which the subjects must focus was restricted to two (Experiment 1). In contrast, prefrontal rats were unable to sustain their attention long enough to detect, and react to, subtle variations in brightness (Experiment 2). This result suggests a dissociation between different types of attentional functions depending upon the integrity of the PFC. More specifically, results in Experiment 2 suggest an involvement of the PFC in sustained attention. Finally, the overall results show that even in tasks involving low demands on response selection the PFC is involved in attentional functions.

Two groups of six cats were subjected to a spatial learning task in cross-mazes that differed only in the spatial relationship between the goal and the single available visual cue. When this cue was remote from the goal (“mapping situation”), the cats did not need more testing days to reach the learning criterion than when it was above the goal (“guidance situation”). Additional behavioural data gave evidence of two information-gathering strategies within each group: the first consisted of taking the relevant information from the starting point; the second was to choose the correct path from the central choice-point. These strategies were discussed in the light of O'Keefe and Nadel's theory (1978) concerning two spatial behaviours, mapping and route-following.The results of a second experiment showed that the cats subjected to the mapping situation were markedly less affected than those subjected to the guidance situation by a delay introduced between the moment when the relevant cue was still available and the moment when the subjects were allowed to run to the goal.In a third experiment, it was shown that only cats that were seen as choosing their path from the starting point during learning (Experiment 1) succeeded in using short-cuts: subjects that chose from the central choicepoint needed to pass through this place when a shorter path was available.These results show that the processes involved in spatial behaviours may be characterized by taking into account some of the behavioural components. Furthermore, the properties of these processes can be assessed with additional experiments, such as delayed-reaction tasks and short-cutting tests.