Sensorimotor Function Assays

Balance Beam

Motor coordination is assessed as the latency to cross the balance beam and the number of slips made while crossing (28, 29). Typically, several beams of varying difficulty (the thinner the beam, the harder the task) are used and introduced in a randomized design.

Grip Strength

Motor function can be assessed as the latency to fall when suspended from a wire (30-34). We have also developed a more sensitive measure of grip using the latency to release various weights when the weight is held in the forepaw using several weights (35).

Parallel Rod Floor

The parallel rod floor test automatically assesses motor coordination and allows the simultaneous measurement of ataxia and locomotor activity. It measure foot faults (slips from the rods to the contact plate below) over the total distance traveled (assessed by a camera and tracking software) (36).

Rotarod

Analyzing the latency to fall from a rotating, accelerating rod can test motor coordination.  Motor learning is evident by increased latency to fall over a series of trials, and can be assessed by examining the improvement over time (multiple trials and/or multiple days).  Motor skill memory can also be tested after suitable retention intervals between training and testing trials (37).

Vision

Some tasks that address visual function include the visual cliff and visual placing. The visual cliff assesses a rodent’s reluctance to approach a precipice, with the premise that normally sighted animals will not cross to the apparent drop. Visual placing utilizes a rodent’s natural inclination to reach for a substrate when suspended by the tail (38-40).

Gait Analysis

Using a high-speed camera and footprint identification software (41), measures of gait and stance can be assessed across lifespan, at different developmental stages, in genetically engineered or surgically manipulated subjects (42).

Tape Removal Test – Fine Motor Coordination

Subtle deficits in fine motor coordination and sensorimotor function can be assessed by the adhesive tape removal test. First developed to investigate stimulus-directed movement asymmetries resulting from unilateral nigrostriatal damage, the adhesive removal test is now commonly used to assess deficits in fine motor coordination and sensory function in many other models. The primary measures are the latency to contact the tape (contact latency) and the latency to remove the tape (removal latency) – that reflect sensory and fine motor function respectively (43, 44).

Sunflower Seed Test – Skilled Forelimb and Oromotor Function

Rats and mice typically manipulate a sunflower seed with their forelimbs, bite a corner of the seed or split it longitudinally (into two pieces), and then eat the seed (45, 46). An intact subject can typically shell and eat five seeds in approximately 30–35 s with an average of few leftover shell pieces (47). However, limb and oromotor deficits can interfere with this process, leading to increased shell pieces and increased time to complete the task (47).

References

  1. Stanley, JL, Lincoln, RJ, Brown, TA, McDonald, LM, Dawson, GR and Reynolds, DS (2005). “The mouse beam walking assay offers improved sensitivity over the mouse rotarod in determining motor coordination deficits induced by benzodiazepines.” J Psychopharmacol 19(3): 221-227 [PMID: 15888506]
  2. Boehm, SL, Schafer, GL, Phillips, TJ, Browman, KE and Crabbe, JC (2000). “Sensitivity to Ethanol-Induced Motor Incoordination in 5-HT1B Receptor Null Mutant Mice Is Task-Dependent: Implications for Behavioral Assessment of Genetically Altered Mice.” Behavioral Neuroscience 114(2): 401 [PMID:
  3. Murphy, MP, Rick, JT, Milgram, NW and Ivy, GO (1995). “A simple and rapid test of sensorimotor function in the aged rat.” Neurobiol Learn Mem 64(2): 181-186 [PMID: 7582826]
  4. Crawley, JN (1999). “Behavioral phenotyping of transgenic and knockout mice: experimental design and evaluation of general health, sensory functions, motor abilities, and specific behavioral tests.” Brain Res 835(1): 18-26 [PMID: 10448192]
  5. van Riezen, H and Boersma, L (1969). “A new method for quantitative grip strength evaluation.” European Journal of Pharmacology 6(3): 353 [PMID:
  6. Ingram, DK, London, ED, Reynolds, MA, Waller, SB and Goodrick, CL (1981). “Differential effects of age on motor performance in two mouse strains.” Neurobiology of Aging 2(3): 221 [PMID:
  7. Schulze, GE and Boysen, BG (1991). “A neurotoxicity screening battery for use in safety evaluation: Effects of acrylamide and 3′,3′-iminodipropionitrile.” Fundamental and Applied Toxicology 16(3): 602 [PMID:
  8. Deacon, RM (2013). “Measuring the strength of mice.” J Vis Exp (76)[PMID: 23770643] [PMC3725666].
  9. Kamens, HM and Crabbe, JC (2007). “The parallel rod floor test: a measure of ataxia in mice.” Nat Protoc 2(2): 277-281 [PMID: 17406586]
  10. Mann, A and Chesselet, M-F (2015). Chapter 8 – Techniques for Motor Assessment in Rodents. Movement Disorders (Second Edition). MS LeDoux. Boston, Academic Press: 139-157.
  11. Routtenberg, A and Glickman, SE (1964). “Visual Cliff Behavior in Albino and Hooded Rats.” J Comp Physiol Psychol 58: 140-142 [PMID: 14197028]
  12. Gibson, EJ and Walk, RD (1960). “The “visual cliff”.” Sci Am 202: 64-71 [PMID: 13827949]
  13. Pinto, LH and Enroth-Cugell, C (2000). “Tests of the mouse visual system.” Mamm Genome 11(7): 531-536 [PMID: 10886018]
  14. Mendes, CS, Bartos, I, Marka, Z, Akay, T, Marka, S and Mann, RS (2015). “Quantification of gait parameters in freely walking rodents.” BMC Biol 13: 50 [PMID: 26197889] [PMC4511453].
  15. Dai, M, Liou, B, Swope, B, Wang, X, Zhang, W, Inskeep, V, Grabowski, GA, Sun, Y and Pan, D (2016). “Progression of Behavioral and CNS Deficits in a Viable Murine Model of Chronic Neuronopathic Gaucher Disease.” PLoS One 11(9): e0162367 [PMID: 27598339] [PMC5012639].
  16. Freret, T, Bouet, V, Leconte, C, Roussel, S, Chazalviel, L, Divoux, D, Schumann-Bard, P and Boulouard, M (2009). “Behavioral deficits after distal focal cerebral ischemia in mice: Usefulness of adhesive removal test.” Behav Neurosci 123(1): 224-230 [PMID: 19170448]
  17. Bouet, V, Boulouard, M, Toutain, J, Divoux, D, Bernaudin, M, Schumann-Bard, P and Freret, T (2009). “The adhesive removal test: a sensitive method to assess sensorimotor deficits in mice.” Nat Protoc 4(10): 1560-1564 [PMID: 19798088]
  18. Whishaw, IQ, Sarna, JR and Pellis, SM (1998). “Evidence for rodent-common and species-typical limb and digit use in eating, derived from a comparative analysis of ten rodent species.” Behav Brain Res 96(1-2): 79-91 [PMID: 9821545]
  19. Whishaw, IQ and Coles, BL (1996). “Varieties of paw and digit movement during spontaneous food handling in rats: postures, bimanual coordination, preferences, and the effect of forelimb cortex lesions.” Behav Brain Res 77(1-2): 135-148 [PMID: 8762164]