Raymond P. Kesner, Bridget L. Bolland, Manoli Dakis Memory for Spatial Locations, Motor Responses, and Objects: Triple Dissociation among the Hippocampus, Caudate Nucleus, and Extrastriate Visual Cortex Raymond P. Kesner, Bridget L. Bolland, Manoli Dakis Group A7: Snir Seitelbach, Dave Dudar, Scott Good, Katie Herdman, Monika Walerjan

OUTLINE INTRODUCTION METHOD RESULTS & DISCUSSION CRITIQUES NEXT STEPS Overall Motive of the Experiment Background Inadequate Research Adequate Research METHOD Pros Cons RESULTS & DISCUSSION CRITIQUES Hippocampus Lesions Caudate Nucleus Lesions Extrastriate Visual Cortex Lesions NEXT STEPS REFERENCES

INTRODUCTION Overall Motive of the Experiment Snir Seitelbach INTRODUCTION Overall Motive of the Experiment To prove there are multiple memory systems Attribute Database Memory Model Working & Declarative Memory Model Different neural substrates that mediate different attributes Hippocampus exclusively codes all information (spatial, temporal, response, sensory-perceptual, or affect)

BACKGROUND Inadequate Research Snir Seitelbach BACKGROUND Inadequate Research “Equivalent impairment of spatial and nonspatial memory following damage to the hippocampus” - Cave and Squire Our study claimed Cave and Squire thought humans with demonstrated hippocampal damage show deficits in spatial memory tasks Conclusion of study above: Hippocampus is not especially involved in spatial memory

BACKGROUND Inadequate Research Snir Seitelbach BACKGROUND Inadequate Research “A note on spatial-motor deficits in patients with Huntington’s disease: a test of a hypothesis” - Potegal In Our Study: labeled as a deficit in memory. Health Canada defines Huntington’s disease as a neuronal degeneration disorder that involves functional deficit.

BACKGROUND Adequate Research Snir Seitelbach BACKGROUND Adequate Research “Limbic lesions and the problem of stimulus-reinforcement associations” - Jones & Mishkin Hippocampal lesions in monkeys produce severe deficits in spatial location memory tasks

BACKGROUND Adequate Research Snir Seitelbach BACKGROUND Adequate Research “The contributions of positions, direction and velocity to single unit activity in the hippocampus of freely moving rats” - McNaughton, Barnes, & O’Keefe In both monkeys and rodents many hippocampi cells increase their firing rate when an animal is located a specific place within a specific environment or is attempting to locate a stimulus in a particular location

METHOD Katie Herdman EXPERIMENT 1 EXPERIMENT 2 EXPERIMENT 3 Spatial Location Memory Task Motor Response Memory Task Visual Object Memory Task

METHOD Pros The radial arm maze in Experiment 1 Katie Herdman METHOD Pros The radial arm maze in Experiment 1 is an adequate method for testing spatial location memory as established by previous studies. Modification of Experiment 3 to allow for direct comparisons with the same analogous procedures used in monkeys.

Katie Herdman METHOD Pros Verification of lesions to show consistent damage across all three experiments.

METHOD Cons Sample size was small for each lesioned Katie Herdman METHOD Cons Sample size was small for each lesioned groups in each experiment. The sample size was not the same for all lesioned groups.

METHOD Cons Lesion verification showed damage to Katie Herdman METHOD Cons Lesion verification showed damage to primary striate visual cortex, affecting rat’s vision during Experiment 3.

The Primary Visual Cortex Katie Herdman The Primary Visual Cortex V1 is uniquely positioned as the primary distributor of most visual information that reaches other cortical areas In absence of V1, visual signals still reach many extrastriate areas, but seem incapable of generating normal conscious experiences (Tong, 2003)

Katie Herdman METHOD Cons Acid lesioning may be more preferable instead of electrolytic lesioning because it is more accurate Kainic Acid

A Different Method for Lesioning Katie Herdman A Different Method for Lesioning “In situ injection of kainic acid: a new method for selectively lesioning neural cell bodies while sparing axons of passage” - Coyle, Molliver & Kuhar These morphologic studies provide direct evidence that injection of kainic acid in brain causes a selective degeneration of neurons will cell bodies in the area of the injection but spares axons that pass through or terminate in the injected area. (Coyle et al., 1978)

RESULTS & DISCUSSION Critiques Scott Good RESULTS & DISCUSSION Critiques Hippocampal Lesions: Mice unable to perform well in spatial memory tasks, but performed well on the other tasks. This supports the attribute model.

RESULTS & DISCUSSION Critiques Scott Good RESULTS & DISCUSSION Critiques Hippocampal Lesions: A recent study made an observation on the hippocampus’ function: it is only responsible for spatial memory. This is a large generalization.

RESULTS & DISCUSSION Critiques Scott Good RESULTS & DISCUSSION Critiques Hippocampal Lesions: the hippocampus is responsible for processing memory. The rats were retested seconds-to-minutes after the learning process. A longer wait would have showed deficits in all the experimental procedures.

RESULTS & DISCUSSION Critiques Scott Good RESULTS & DISCUSSION Critiques Caudate Nucleus Lesions: responding do a visual stimulus requires egocentric knowledge of the location of the stimulus. Many cells responsible for this cognitive ‘roadmap’ are found in the posterior parietal cortex, but this was not addressed.

RESULTS & DISCUSSION Critiques Scott Good RESULTS & DISCUSSION Critiques Caudate Nucleus Lesions: Cells in the caudate nucleus respond to other stimuli such as smell, sound and sight. Lesions in the caudate nucleus would affect these senses, most importantly the rat’s ability to see to respond.

RESULTS & DISCUSSION Critiques Scott Good RESULTS & DISCUSSION Critiques Extrastriate Visual Cortex Lesions: mice had difficulty in non-matching to sample tasks Evidence supports the attribute model

RESULTS & DISCUSSION Critiques Scott Good RESULTS & DISCUSSION Critiques Extrastriate Visual Cortex Lesions: object recognition test should have had controls Comparison to apperceptive agnosia is confusing Role of hippocampus may have been underestimated for long term memory formation (Squire & Zola-Morgan, 1991)

Snir Seitelbach NEXT STEPS… Less bias toward one specific model (Kessner is the author of the study and the creator of the attribute model…hmmmm?) A much larger sample size: study did not have a lot of power More accurate lesioning More scientific method for object-discrimination task.

REFERENCES Cave, C.B. & Squire, L.R. (1991). Equivalent impairment of spatial and nonspatial memory following damage to the human hippocampus. Hippocampus 1: 329-340. Coyle, J.T., Molliver, M.E., & Kuhar, M.J. (1978). In situ injection of kainic acid: a new method for selectively lesioning neural cell bodies while sparing axons of passage. J Comp Neurol. 180 (2): 301-323 Firth, C. D. (2000). Abnormalities in the Awareness and Control of Action. Biological Sciences. 355 (1404): 1771-1788. Howell, D. (2008). Fundamental Statistics for the Behavioural Sciences. Belmont, CA : Thomson/Wadsworth, 6th ed. Jones, B. & Mishkin, M. (1972). Limbic lesions and the problem of stimulus reinforcement associations. Exp Neurol 36: 362-377. McNaughton, B.L., Barnes, C.A., O’Keefe, J. (1983). The contribution of position, direction and velocity to single unit activity in the hippocampus of freely moving rats. Exp Brain Res 52: 41-49. Milner, A. D. et. al. (1999). A Paradoxical Improvement of Misreaching in Optic Ataxia: New Evidence for Two Separate Neural Visual Systems for Visual Localization. Biological Sciences. 266 (1434): 2225-2229. Squire, L.R. & Zola-Morgan, S. (1991). The medial temporal lobe memory system. Science. 253: 1380-1386. Tong, F. (2003). Primary Visual Cortex and Visual Awareness. Neuroscience. 4, 219-229.

THANK YOU For Your TIME and ATTENTION!