Learning in the Fast Lane: New Insights into Neuroplasticity

Abstract

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.

Structural and functional neuroplasticity in human learning of spatial routes

“…The findings also show that we may not yet have reached the lower limit on how much training is necessary to produce such changes, indicating remarkably rapid short-term structural neuroplasticity of the hippocampus. The study provides an important, independent confirmation of the meticulous previous work carried out in a single laboratory (Blumenfeld-Katzir et al, 2011;Sagi et al, 2012;Hofstetter et al, 2013;Tavor et al, 2013). Like the previous work, this study shows that the magnitude of diffusivity changes in hippocampus are significantly related to the behaviorally-measured magnitude of the learning changes.…”

“…The landmark sorting task was scored by following the general procedure reported by Sagi et al (2012). For each of the eight screenshots in each test, one point was given for each of the other screenshots that it correctly preceded in the participants sorting response.…”

“…These findings of neuroplasticity have been extended to humans and to shorter training episodes in a series of recent papers from the same laboratory (Sagi et al, 2012;Hofstetter et al, 2013;Tavor et al, 2013). Sagi et al trained both rats and humans on a spatial route-learning task for 2 h, comparing diffusion-weighted imaging before and after the training.…”

Studying neuroanatomy using MRI

“…Additional evidence came from studies showing that teaching adults how to juggle altered grey-matter concentrations in the visual and parietal cortex 55 , a change that occurred in as quickly as seven days 56 , and was accompanied by changes in water diffusion in underlying white matter 57 . Microstructural changes have even been detected using diffusion MRI within two hours of playing a video game 58 . Further work by multiple groups has shown that MRI can detect brain plasticity in motor coordination tasks 59 and musical training 60 amongst others.…”

Diffusion magnetic resonance imaging for Brainnetome: A critical review

“…Intensive training of normal controls for ~6 weeks changes WMM through induction of long-term potentiation (LTP) [131] . Excitingly, a more recent study showed that short-term training for only two hours results in microstructural changes in the brain that can be detected by a general DTI framework [132] . This demonstrates that the dMRI technique is able to recapitulate the evolution of a network within a relatively short time-scale.…”