Figure 4.

SAH induces working reference memory dysfunction on Novel Object Recognition (NOR) assessment associated with predominantly moderate cellular damage in hippocampal regions CA1 and the dentate hilus (DH). A: Representative traces demonstrating reduced movement and interaction in SAH animals (square = novel object, circle = familiar object). B: The amount of time SAH rats spent exploring either object was diminished, suggesting impaired sensorimotor and exploratory function. SAH rats also spent less time investigating the novel object relative to time spent investigating the familiar object. C: Discrimination ratio was decreased in animals following SAH, consistent with impaired reference memory. D: Total distance moved during the NOR task was reduced in SAH rats. E: Examination of the DH and CA1 regions of the hippocampus revealed presence of severe damage (red outline) and moderate damage (blue outline) with a greater relative proportion of moderate damage. Black bar = 100μm; white bar = 25μm; red arrowheads = unhealthy cells; blue arrows = examples of healthy cells; solid outline = 20x = 0.2mm²; dashed outline = 40x = 0.01mm²; * P < 0.05, **** P < 0.0001, mixed-effects ANOVA.