Fimbria–Fornix vs Selective Hippocampal Lesions in Rats: Effects on Locomotor Activity and Spatial Learning and Memory

Cassel, Jean‐Christophe; Cassel, Suzanne L.; Galani, Rodrigue; Kelche, Christian; Will, Bruno; Jarrard, Leonard E.

doi:10.1006/nlme.1997.3807

Cited by 138 publications

(76 citation statements)

References 27 publications

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“…Two cohorts of rats with descending postcommissural fornix lesions (dPFx) were tested on spatial memory tasks sensitive to the loss of the hippocampus, fornix, anterior thalamic nuclei, and mammillary bodies (e.g., Warburton et al, 1997;Cassel et al, 1998;Bannerman et al, 2002;Vann and Aggleton, 2003). Taken together, the dPFx rats were unimpaired on the delayedmatching-to-place task in the water-maze.…”

Section: Discussionmentioning

confidence: 99%

Selective disconnection of the hippocampal formation projections to the mammillary bodies produces only mild deficits on spatial memory tasks: Implications for fornix function

et al. 2011

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ABSTRACT:It is now clear that the integrity of the fornix is important for normal mnemonic function. The fornix, however, is a major white matter tract, carrying numerous hippocampal formation afferents and efferents, and it is not known which specific components support memory processes. Established theories of extended hippocampal function emphasize the sequential pathway from the hippocampal formation (i.e., subicular complex) to the mammillary bodies and, thence, to the anterior thalamus, as pathology in each of these structures is implicated in anterograde amnesia in humans and spatial memory deficits in rats. The specific importance of the hippocampal formation projections that just innervate the mammillary bodies has, however, never been tested. This study isolated these specific projections in the rat by selectively cutting the descending component of the postcommissural fornix. Two successive, cohorts of rats with these tract lesions were tested on working memory tasks in the water-maze, T-maze, and radial-arm maze. Disconnecting the descending postcommissural fornix had only a mild effect or sometimes no apparent effect on the performance of these spatial memory tasks, even though tracing experiments confirmed the loss of hippocampal formation-mammillary projections. One implication is that the spatial deficits found in rats following standard fornix lesions are only partly attributable to the loss of projections from the hippocampal formation to the mammillary bodies. Perhaps more surprising, the behavioral impact of cutting the descending postcommissural fornix in rats appeared appreciably less than the effect of either mammillary body or mammillothalamic tract lesions. The present experiments show that the mammillary bodies can still effectively support spatial memory in the absence of their dense subicular complex inputs, so revealing the importance of the other afferents for sustaining mammillary body function. This new evidence for independent functions shows that the mammillary bodies are more than just a hippocampal relay. V V C 2010 Wiley-Liss, Inc.

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Section: Discussionmentioning

confidence: 99%

Selective disconnection of the hippocampal formation projections to the mammillary bodies produces only mild deficits on spatial memory tasks: Implications for fornix function

et al. 2011

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“…It may be also necessary for the functional integrity of the circuits in which new cells are born. In fact, hippocampal lesions or disruptions of the function of the hippocampus impair spatial working memory (Cassel et al, 1998;Lee et al, 2002). Therefore, it is known that newborn neurons contribute to synaptic plasticity (LTP) in the DG (Saxe et al, 2006;Snyder et al, 2001;Zhao et al, 2003).…”

Section: Learning and Memory 'Cognitive Functionsmentioning

confidence: 99%

Adult Hippocampal Neurogenesis and Memory

Ortega-Martínez

2017

Int J Adv Biol Biom Res.

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“…An alternative maze configuration in which only some of the eight arms are baited allows to evaluate reference memory besides working memory through recording of the number of reference memory errors (number of entries into unbaited arms) and working memory errors (re-entry into an already visited arm). Performance in the Olton maze requires an adequate functioning of hippocampalprefrontocortical neuronal circuits, and is a reliable parameter of morpho-functional integrity of these brain structures after ischemia and neuroprotection (Cassel et al, 1998;Fritts et al, 1998;Izaki et al, 2008;Kolb, 1990, Kolb et al 1982Laroche et al, 2000;Olton et al, 1982;Seamans et al, 1995;Winocur, 1982). An aquatic version of the 8-arm radial maze has also been described (Kolb et al, 1982), and used to correlate hippocampal pyramidal neurons damage and working memory performance (Nelson et al 1997).…”

Section: Cognitive Functions Assessmentmentioning

confidence: 99%