Brain activity during observation and motor imagery of different balance tasks: An fMRI study

Abstract

After immobilization, patients show impaired postural control and increased risk of falling. Therefore, loss of balance control should already be counteracted during immobilization. Previously, studies have demonstrated that both motor imagery (MI) and action observation (AO) can improve motor performance. The current study elaborated how the brain is activated during imagination and observation of different postural tasks to provide recommendations about the conception of non-physical balance training. For this purpose, participants were tested in a within-subject design in an fMRI-scanner in three different conditions: (a) AO + MI, (b) AO, and (c) MI. In (a) participants were instructed to imagine themselves as the person pictured in the video whereas in (b) they were instructed simply to watch the video. In (c) subjects closed their eyes and kinesthetically imagined the task displayed in the video. Two tasks were evaluated in each condition: (i) static standing balance and (ii) dynamic standing balance (medio-lateral perturbation). In all conditions the start of a new trial was indicated every 2 sec by a sound. During AO + MI of the dynamic task, participants activated motor centers including the putamen, cerebellum, supplementary motor area, premotor cortices (PMv/d) and primary motor cortex (M1). MI showed a similar pattern but no activity in M1 and PMv/d. In the SMA and cerebellum, activity was generally higher in the dynamic than in the static condition. AO did not significantly activate any of these brain areas. Our results showed that (I) mainly AO + MI, but also MI, activate brain regions important for balance control; (II) participants display higher levels of brain activation in the more demanding balance task; (III) there is a significant difference between AO + MI and AO. Consequently, best training effects should be expected when participants apply MI during AO (AO + MI) of challenging postural tasks.

Task-dependent changes of corticospinal excitability during observation and motor imagery of balance tasks

“…The pattern of MEP modulation with the highest activity during AO + MI of the dynamic task and hardly any activity during passive AO is therefore very similar to the general pattern of brain activity derived from our recent fMRI measures (Taube et al, 2015). In this previous study, we used exactly the same experimental design as in the current study to make direct comparisons possible.…”

“…Using another analysis such as small volume correction on a ROI improves the sensitivity and induces a better detection of M1 activity, especially in complex designs with multiple conditions. Using this kind of analysis, Sharma et al (2008) and Taube et al (2015) detected activity in the primary motor cortex during mental simulation. However, although significant activation was detected during AO + MI of balance tasks, no graded activity that depended on the task difficulty or the mental simulation technique (AO + MI, MI, passive AO) could be observed (Taube et al, 2015).…”

“…The study design (balance tasks and mental simulation conditions) resembled the one we used in a recent fMRI study (Taube et al, 2015) in order to allow direct comparisons. We hypothesized that corticospinal facilitation would be most pronounced during AO + MI and less prominent during passive AO.…”

Using the Force: STEM Knowledge and Experience Construct Shared Neural Representations of Engineering Concepts

“…For novices at run 4, this network is localized dorsally, in some of the same regions for novices at the end of the experiment that it appears for engineering students at both time points: in particular, in precuneus and intraparietal sulcus. This may be an indication that novices have begun to engage motor imagery as a means of grasping the concepts of Newtonian force (Calvo-Merino, 2004;Hétu et al, 2013;Kontra et al, 2015;Pilgramm et al, 2016;Schlegel et al, 2013;Taube et al, 2015). However, given their lack of NEURAL REPRESENTATIONS OF ENGINEERING CONCEPTS 35 hands-on experience mapping this concept onto physical engagement, the way the engineering students have done in lab and classroom demonstrations, it is expected that for the novices this mapping would be less veridical and therefore not involve the retrieval of perceptual memories.…”

Clinical Application of Motor Imagery Training

“…This suggested that motor imagery alone is more effective than action observation therapy combined with motor imagery for novel motor learning. As evidence of the effectiveness of action observation plus motor imagery, in neuroscience data, Taube et al have shown that greater activation in the mirror neuron system was obtained when subjects observed the movement of others during which time subjects imagined their own body movement in terms of the model's movement [78].…”