Visually guided locomotion, distractibility, and the missing-stimulus effect in hooded rats with unilateral or bilateral lesions of parietal cortex.

Abstract

Hooded rats with bilateral lesions of the anterior part of the hippocampal formation (HIP), anterior region of the posterior parietal cortex (APC), or posterior region of the posterior parietal cortex (PPC) were compared with controls for their exploration of 5 objects in an open field, habituation of locomotion and object investigation, and response to spatial and nonspatial change. First, all groups displayed habituation of both locomotor and exploratory activity. Second, controls selectively reexplored displaced objects, and APC-lesioned rats reexplored all objects, whereas PPC- and HIP-lesioned rats failed to react to the spatial change. Third, a novel object induced reexploration in all groups. The results are consistent with the roles of the HIP and PPC in spatial information processing. Moreover, the APC and PPC are involved in attentional effortful processing and visuospatial information processing necessary for spatial representation, respectively.

Gamma Oscillations in Rat Hippocampal Subregions Dentate Gyrus, CA3, CA1, and Subiculum Underlie Associative Memory Encoding

“…Rats explored these swapped objects (mean number of events ± SEM across rats = 80.7 ± 5.6) for a different amount of time than repeated (20.3 ± 1.4 events) or novel objects (n = 20.3 ± 1.4 events) in control conditions [F(2,10) = 10.93, p = 0.003, partial eta 2 = 0.686]. Specifically, rats explored swapped objects for a longer duration than objects repeated in the same location [t(5) = 3.45, p = 0.018, d = 1.41] but less than novel objects on lap 3 [t(5) = 3.20, p = 0.024, d = 1.30], indicating that rats had memory for the prior locations of objects, similar to previous reports (e.g., Save et al, 1992). …”

Aging impairs hippocampus-dependent long-term memory for object location in mice

“…We assessed hippocampal function and spatial memory formation in aged mice by using a hippocampus-dependent object place recognition task (Mumby, et al, 2002, Oliveira, et al, 2010, Save, et al, 1992). Training consisted of three 10-minute exposures (3 minute inter-trial interval) to an arena that contained two distinct objects (Fig.…”

“…The present studies focus on object memory tasks, which are ideal to study both short- and long-term memory formation because learning occurs within a single session (Baker and Kim, 2002, de Lima, et al, 2006, Oliveira, et al, 2010). Furthermore, object-based tasks take advantage of the innate tendency of mice to explore novel items in their environment, while inflicting little stress on the animals (Save, et al, 1992, Sharma, et al, 2010), and the anatomical substrates underlying object memory are well characterized (Ennaceur and Aggleton, 1997, Oliveira, et al, 2010, Roozendaal, et al, 2010). …”

Kctd13 deletion reduces synaptic transmission via increased RhoA

“…See Supplementary Table 1 for detailed statistics. All behaviour tests were performed essentially as previously described except as noted below 53–62 .…”