L1.2 Locomotion

Question 1

What is Gait?

Answer 1

pattern of walking (allows diagnosis of neural properties)

Question 2

2 main types of human gait?

Answer 2

• Walk: Inverted pendulum (efficient)
  
  • Joint makes limbs shorter → walk better
• Impulsive run: exploits energy stored in muscles
  
  • Bounces off ground

Question 3

Why are Chimpanzee’s bipedal walk less efficient than humans?

Answer 3

• Main mass not over Line of gravity (LoG)

Question 4

What is the spinal role in locomotion?

Answer 4

• 1) Pattern generation
  
  • Reciprocally connected interneurons in spinal cord → produce phasic patterns
• 2) Modulation of gait cycle by sensory inputs (including nociceptive)
• 3) ↑ signal from brainstem = ↑rate of locomotor triggering gait transition

Question 5

What is the role of foetal locomotive activities?

Answer 5

• Refine neural networks → optimise
• Helps develop muscle & joints

Question 6

How are decerebrated cats still able to increase their speed accordingly?

Answer 6

• *stretching of iliopsoas muscles mid extension → detected by muscle spindle reflex → alters speed to accommodate*
• Cannot initiate/generate gait transitions and patterns → cannot go past obstacles