Memory relationships between MRI volumes and resting PET metabolism of medial temporal lobe structures

• Published in: Epilepsy & behavior Vol. 5; no. 5; pp. 669 - 676
• Main Authors: Griffith, H. Randall, Pyzalski, Robert W., Seidenberg, Michael, Hermann, Bruce P.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01-10-2004
• Subjects: Adolescent; Adult; Electroencephalography; Epilepsy, Complex Partial - physiopathology; Epilepsy, Temporal Lobe - physiopathology; Female; Fluorodeoxyglucose F18; Hippocampus; Hippocampus - anatomy & histology; Hippocampus - diagnostic imaging; Humans; Image Processing, Computer-Assisted; Magnetic Resonance Imaging; Male; Memory - physiology; Middle Aged; MRI volumetrics; Paired-Associate Learning - physiology; Parahippocampal Gyrus - anatomy & histology; Parahippocampal Gyrus - diagnostic imaging; Positron emission tomography; Psychomotor Performance - physiology; Radiopharmaceuticals; Temporal Lobe - anatomy & histology; Temporal Lobe - diagnostic imaging; Temporal Lobe - metabolism; Temporal lobe epilepsy; Verbal Learning - physiology; Verbal memory; Verbal memory; Temporal lobe epilepsy; MRI volumetrics; Positron emission tomography; Hippocampus
• ISSN: 1525-5050; 1525-5069
• DOI: 10.1016/j.yebeh.2004.06.020

Prior studies of temporal lobe epilepsy (TLE) patients showed that MRI volumes and resting PET scan measures of temporal lobe structures were related to memory. Weintrob and colleagues [Ann. Neurol. 2002;51:442–7] reported that PET glucose uptake in the left perirhinal cortex predicted verbal paired associate (PA) learning, whereas MRI volume of the left hippocampus did not. We investigated whether MRI volumes could account for memory functioning if both PET and volumes were from the same region in 18 TLE patients. Volumes and glucose uptake of the hippocampus and parahippocampal gyrus (PHG) were compared with WMS-III performance. Significant correlations were observed between hippocampal volumes and PA and Logical Memory (LM) Percent Retention, but not between memory and PHG volumes or any PET measures. Multiple regression revealed that hippocampal volumes, but not PHG volumes or PET, significantly predicted PA and LM retention scores. These findings suggest that hippocampal volumes provide unique information regarding memory.