Learning in the Fast Lane: New Insights into Neuroplasticity

• Published in: Neuron (Cambridge, Mass.) Vol. 73; no. 6; pp. 1195 - 1203
• Main Authors: Sagi, Yaniv, Tavor, Ido, Hofstetter, Shir, Tzur-Moryosef, Shimrit, Blumenfeld-Katzir, Tamar, Assaf, Yaniv
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 22.03.2012; Elsevier Limited
• Subjects: Adult; Analysis of Variance; Animals; Anisotropy; Brain; Brain - anatomy & histology; Brain - metabolism; Brain - physiology; Brain Mapping; Cognition & reasoning; Computed tomography; Diffusion Tensor Imaging; Female; Hippocampus; Humans; Imaging, Three-Dimensional; Learning; Learning - physiology; Limbic system; Magnetic Resonance Imaging; Male; Memory; Microscopy; Nerve Tissue Proteins - metabolism; Neuronal Plasticity - physiology; NMR; Nuclear magnetic resonance; parahippocampus; Plasticity (functional); Plasticity (neural); Rats; Rats, Wistar; Rodents; Space Perception - physiology; Spatial discrimination learning; spatial memory; Statistical analysis; Studies; Time Factors; Variance analysis; Video Games; Young Adult
• ISSN: 0896-6273; 1097-4199; 1097-4199
• DOI: 10.1016/j.neuron.2012.01.025

The timescale of structural remodeling that accompanies functional neuroplasticity is largely unknown. Although structural remodeling of human brain tissue is known to occur following long-term (weeks) acquisition of a new skill, little is known as to what happens structurally when the brain needs to adopt new sequences of procedural rules or memorize a cascade of events within minutes or hours. Using diffusion tensor imaging (DTI), an MRI-based framework, we examined subjects before and after a spatial learning and memory task. Microstructural changes (as reflected by DTI measures) of limbic system structures (hippocampus and parahippocampus) were significant after only 2 hr of training. This observation was also found in a supporting rat study. We conclude that cellular rearrangement of neural tissue can be detected by DTI, and that this modality may allow neuroplasticity to be localized over short timescales. ► Two hours of learning causes mean diffusivity reduction in the human hippocampus ► Diffusion MRI can be used to study short-term structural neuroplasticity ► Diffusion MRI changes following learning can be linked to BDNF expression ► Diffusion MRI allows multiregional assessment of structural plasticity Using DTI, Sagi et al. find significant microstructural changes in human limbic structures after only 2 hr of spatial learning training, suggesting that neural tissue rearrangement can be detected and localized over very short timescales.