We studied the response to axial taps (mini-perturbations) of a group of 13 healthy older subjects (mean age 63 ± 12 years, 7 females, 6 males), 12 of whom were also studied using larger applied (macro-) perturbations requiring active postural responses. The mini-perturbation consisted of a brief impulsive force produced by a mini-shaker applied to the trunk at the level of the shoulders and anteriorly at the upper sternum which was perceived as a tap. Acceleration, force platform, and EMG measurements were made. The average peak accelerations for the mini-perturbations were 108 mG (anterior) and − 78.9 mG (posterior). Responses overall were very similar to those previously reported for younger subjects: the perturbation evoked short latency responses in leg muscles, modulated by degree and direction of lean, and were largest for the muscle most relevant for the postural correction. The increases in the amplitude for the main agonist were greater than the increase in tonic activity. With both anterior and posterior lean, co-contraction responses were present. The size of the EMG response to the mini-perturbations correlated with the corresponding earliest EMG responses (0–100, 100–200 ms intervals) to the larger postural perturbations, timing which corresponds to balance responses. The balance responses evoked by the larger imposed postural perturbations may, therefore, receive a contribution through the reflex pathway mediating the axial tap responses, whose efferent limb appears to be the reticulospinal tract.
This is a preview of subscription content, access via your institution.
Buy single article
Instant access to the full article PDF.
Price excludes VAT (USA)
Tax calculation will be finalised during checkout.
Bisdorff AS, Bronstein AM, Wolsley C, Gresty MA, Davies A, Young A (1999) EMG responses to free fall in elderly subjects and akinetic rigid patients. J Neurol Neurosurg Psychiat 66:447–455
Bloem BR, Allum JHJ, Carpernter MG, Honegger F (2000) Is lower leg proprioception essential for triggering human automatic postural responses? Exp Brain Res 130:375–391
Bötzel K, Feise P, Kolev OI, Krafczyk S, Brandt T (2001) Postural reflexes evoked by tapping forehead and chest. Exp Brain Res 138:446–451
Britton TC, Day BL, Brown P, Rothwell JC, Thompson PD, Marsden CD (1993) Postural electromyographic responses in the arm and leg following galvanic vestibular stimulation in man. Exp Brain Res 94:143–151
Christensen LO, Petersen N, Andersen JB, Sinkjaer T, Nielsen JB (2000) Evidence for transcortical reflex pathways in the lower limb of man. Prog Neurobiol 62:251–272
Colebatch JG, Govender S, Rosengren SM (2013) Two distinct patterns of VEMP changes with age. Clin Neurophysiol 124:2066–2068
Colebatch JG, Govender S, Dennis DL (2016) Postural responses to anterior and posterior perturbations applied to the upper trunk of standing human subjects. Exp Brain Res 234:367–376
Drew T, Cabana T, Rossignol S (1996) Responses of medullary reticulospinal neurons to stimulation of cutaneous limb nerves during locomotion in intact cats. Exp Brian Res 111:153–168
Govender S, Dennis DL, Colebatch JG (2015) Axially-evoked postural reflexes: influence of task. Exp Brain Res 233:215–228
Graus S, Govender S, Colebatch JG (2013) A postural reflex evoked by brief axial accelerations. Exp Brain Res 228:73–85
Gurfinkel VS, Lipshits MI, Mori S, Popov KE (1981) Stabilization of body position as the main task of postural regulation. Hum Physiol 7:155–165
Henry SM, Fung J, Horak FB (1998) EMG responses to maintain stance during multidirectional surface translations. J Neurophysiol 80:1939–1950
Horak FB, Shupert CL, Dietz V, Horstmann G (1994) Vestibular and somatosensory contributions to responses to head and body displacements in stance. Exp Brain Res 100:93–106
Hunt AL, Sethi KD (2006) The pull test: a history. Mov Disord 21:894–899
Manchester D, Woollacott M, Zederbauer-Hylton N, Marin O (1989) Visual, vestibular and somatosensory contributions to balance control in the older adult. J Gerontol 44:M118-27
Matthews PBC (1986) Observations on the automatic compensation of reflex gain on varying the pre-existing level of motor discharge in man. J Physiol 374:73–90
Moore SP, Rushmer DS, Windus SL, Nashner LM (1988) Human automatic postural responses: responses to horizontal perturbations of stance in multiple directions. Exp Brain Res 73:648–58
Mrachacz-Kersting N, Sinkjaer T (2003) Reflex and non-reflex torque responses to stretch of the human knee extensors. Exp Brain Res 151:72–81
Munhoz RP, Teive HA (2014) Pull test performance and correlation with falls risk in Parkinson’s disease. Arq Neuropsiquiatr 72:587–591
Oude Nijhuis LB, Allum JH, Borm GF, Honegger F, Overeem S, Bloem BR (2009) Directional sensitivity of “first trial” reactions in human balance control. J Neurophsyiol 101:2802–2814
Petersen N, Christensen LO, Morita H, Sinkjaer T, Nielsen J (1998) Evidence that a transcortical pathway contributes to stretch reflexes in the tibialis anterior muscle in man. J Physiol 512:267–276
Peterson BW, Maunz RA, Pitts NG, Mackel RG (1975) Patterns of projection and braching of reticulospinal neurons. Exp Brain Res 23:335–351
Rosengren SM, Govender S, Colebatch JG (2011) Ocular and cervical vestibular evoked myogenic potentials produced by air- and bone-conducted stimuli: comparative properties and effects of age. Clin Neurophysiol 122:2282–2289
Ross S (2007) Introduction to probability methods, 9th edn. Academic, Amsterdam
Rothwell JC (2006) The startle reflex, voluntary movement, and the reticulospinal tract. Clin Neurophysiol Suppl 58:223–231
Shemmell J (2015) Interactions between stretch and startle reflexes produce task-appropriate rapid postural reactions. Front Integr Neurosci 9:2
Shimamura M, Kogure I (1979) Reticulospinal tracts involved in the spino-bulbo-spinal reflex in cats. Brain Res 172:13–21
Shimamura M, Livingston RB (1963) Longitudinal conduction systems serving spinal and brain-stem coordination. J Neurophysiol 26:258–272
Stapley PJ, Drew T (2009) The pontomedullary reticular formation contributes to the compensatory postural responses observed following removal of the support surface in the standing cat. J Neurophysiol 101:1334–1350
Taube W, Schubert M, Gruber M, Beck S, Faist M, Gollhofer A (2006) Direct corticospinal pathways contribute to neuromuscular control of perturbed stance. J Appl Physiol 101:420–429
Teng B, Govender S, Colebatch JG (2017) Postural responses in the upper limbs evoked by axial impulses: a role for reticulospinal projections. Exp Brain Res 235:2235–2242
Torres-Oviedo G, Ting LH (2007) Muscle synergies characterizing human postural responses. J Neurophysiol 98:2144–2156
Verschueren SM, Brumange S, Swinnen SP, Cordo PJ (2002) The effect of aging on dynamic position sense at the ankle. Behav Brain Res 136:593–603
Welgampola MS, Colebatch JG (2001) Vestibulocollic reflexes: normal values and effects of age. Clin Neurophysiol 112:1971–1979
Wingert JR, Welder C, Foo P (2014) Age-related hip proprioceptive declines: effects on postural sway and dynamic balance. Arch Phys Med Rehabil 95:253–261
We are thankful for participants provided by the Neuroscience Research Australia volunteer database.
Conflict of interest
No conflicts of interest, financial or otherwise, are declared by the authors.
Electronic supplementary material
Below is the link to the electronic supplementary material.
Correlations performed for acceleration, EMG and CoP data following C7 stimulation with anterior lean (left half) and sternal stimulation with posterior lean (right half) for our present older subjects and the younger group previously reported (Govender et al., 2015). Both acceleration and reflex amplitudes showed significant correlations with age. For C7 stimulation during anterior lean, peak acceleration amplitudes at the trunk were negatively correlated (smaller) with age (r = -0.5, P = 0.038) and the soleus EMG onset latency became longer (r = 0.6; P = 0.012). For sternal stimulation and posterior lean, acceleration latencies at the trunk became shorter (r = -0.6; P = 0.004) while peak amplitudes showed no significant changes. TA reflex amplitudes became significantly smaller (r = -0.5; P = 0.035) with increasing age. CoP displacements showed no significant changes. (PDF 426 KB)
About this article
Cite this article
Colebatch, J.G., Govender, S. Axial reflexes are present in older subjects and may contribute to balance responses. Exp Brain Res 236, 1031–1039 (2018). https://doi.org/10.1007/s00221-018-5193-7