Harland Hodges

Learn More
Open mazes are primarily designed to measure place learning and memory, using environmental visuospatial cues. However, maze tasks differ along many dimensions, including (1) types of apparatus, which vary from arenas (water maze: WM) to highly structured routes (radial-arm maze: RAM); (2) availability of visuospatial, associative or sensory cues; (3) task(More)
Transitory global cerebral ischaemia induced in rats by four vessel occlusion for 15 min produced substantial loss of CA1 cells in dorsal hippocampus, and minimal damage in other intra- and extrahippocampal forebrain regions examined. Ischaemic rats showed long-lasting deficits in spatial navigation in the water-maze, consisting of impaired learning to(More)
When animals are exposed to a stimulus that has no consequences they are subsequently impaired in learning that this stimulus predicts an important event, such as footshock. This retarding effect of stimulus pre-exposure is called latent inhibition (LI) and is reliably disrupted by amphetamine, antipsychotics having an opposite effect. The present(More)
Functional effects of fetal hippocampal field grafts were assessed in rats with spatial learning and memory impairments following global cerebral ischaemia. Experiment 1 examined effects of grafts dissected from fields CA1 and CA3 at embryonic day 19 and from the dentate gyrus at postnatal day 1. Cell suspensions (15,000 cells/site) were implanted(More)
We have evaluated the physiological and behavioral effects of the CNS-selective nicotinic agonist (E)-N-methyl-4-(3-pyridinyl) -3-butene-1-amine (RJR-2403) using a number of different methods, including 1) reversal of pharmacologically induced amnesia in a step-through passive avoidance paradigm, 2) radial arm maze performance in rats with chemically(More)
BACKGROUND AND PURPOSE Grafts of MHP36 cells have previously been shown to reduce dysfunction after global ischemia in rats. To test their efficacy after focal ischemia, MHP36 cells were grafted 2 to 3 weeks after transient intraluminal middle cerebral artery occlusion (tMCAO) in rats. METHODS MHP36 cells were implanted into the hemisphere contralateral(More)
Spatial deficits were assessed in male Wistar rats which had undergone 4 vessel occlusion for 5, 10, 15 or 30 min. Relationships between the extent of brain damage, the duration of 4-vessel occlusion, and the behavioural impairment consequent upon ischaemia were investigated. Starting 13-18 days after occlusion, rats were trained to find a hidden platform(More)
Animal models of stroke, notably transient middle cerebral artery occlusion (MCAo), are used to assess the efficacy of pharmacological and transplant treatments. Long-term studies (>1 month) of the functional effects of treatments in animal models are required to predict treatments likely to improve dysfunctions associated with stroke damage. These(More)
Transient global cerebral ischaemia in rats causes relatively circumscribed and specific damage to the CA1 pyramidal cells of the dorsal hippocampus, along with a cognitive deficit manifest as difficulties in the performance of a range of spatial learning and memory tasks. Our previous studies have shown that restoration of behavioural performance in(More)
In a novel approach, neural stem cells were transplanted to ameliorate radiation-induced myelopathy in the spinal cords of rats. A 12-mm section of the cervical spinal cord (T2-C2) of 5-week-old female Sprague-Dawley rats was locally irradiated with a single dose of 22 Gy of (60)Co gamma rays. This dose is known to produce myelopathy in all animals within 6(More)