Fig 1.
Image of Balance Master System, alongside a pictorial representation of the sway referencing technique.
(A) Image of Balance Master Clinical Research System (NeuroCom International, Inc., Clackamas, OR, USA). (B)During sway referencing, the support surface rotates about the ankle axis in proportion to AP sway, making the main proprioceptive signal used in postural control inaccurate.
Fig 2.
Image of the angled double cone coil and foot support.
(A) Angled double cone coil (Magstim, Whitland, United Kingdom). (B) Foot support used for active dorsiflexion during TMS.
Fig 3.
Electrode positions for M1 and cerebellar tDCS.
(A) During M1 stimulation, the anode was placed on the leg area motor hotspot, as identified during single-pulse TMS, and reference was placed on the inion. (B) During cerebellar stimulation, the anode was placed on the median line 2cm below the inion and reference was placed on the right buccinator muscle.
Table 1.
Sample means and standard deviations (in parentheses).
Fig 4.
Schematic representation of how the postural control task blocks are separated during each session.
Fig 5.
AP path length across each testing block and each stimulatory condition for young (A & B) and older adults (C & D) during eyes open and eyes closed respectively. Note the different scale in B and D due to greater sway in Eyes Closed conditions.
Fig 6.
AP peak-to-peak sway amplitude.
AP peak-to-peak sway amplitude for young (A & B) and older adults (C & D) during both visual conditions respectively as a function of stimulation condition (sham, cerebellar, M1) and testing block (pre-stimulation, during (DC), after (post0) and 30 minutes after (post30)).
Fig 7.
MPF for young (A & B) and older adults (C & D) during each visual condition respectively as a function of stimulation condition (sham, cerebellar, M1), testing block (pre, DC, post0 and post30) and first and last 30s of each testing block.
Fig 8.
MEP area under the recruitment curve (AURC).
AURC averaged across both legs for (A) young and (B) older adults as a function of stimulation condition and testing block.