4.2 Head Control and Sitting

Question 1

What do spontaneous infant movements (birth–6 mo) indicate?

Answer 1

A healthy developing nervous system; they vary in speed, coordination, and intensity.

Question 2

What are ‘fidgety movements’ and when do they appear?

Answer 2

Small, continuous medium-speed movements of the neck, trunk, and limbs; seen at ~3–5 months and mark typical neurodevelopment.

Question 3

Abnormal early movement patterns can predict what condition?

Answer 3

Cerebral palsy (e.g., cramped, rigid, or absent fidgety movements).

Question 4

When do infants show early postural neck responses?

Answer 4

As early as 1 month old, showing direction-specific neck muscle activity.

Question 5

What are the 4 stages of emerging head/trunk control?

Answer 5

1. Head control with trunk support. 2. Brief propping on arms, some trunk/neck/leg responses. 3. Independent sitting with trunk + leg responses. 4. Standing with coordinated trunk/leg responses (mature strategies).

Question 6

Which sensory systems contribute to postural control?

Answer 6

Visual, vestibular, and somatosensory systems.

Question 7

How does vision affect head control development?

Answer 7

Vision calibrates vestibular + somatosensory inputs; blind infants show delays in head orientation by ~2–3 months.

Question 8

How does the vestibular system influence posture?

Answer 8

Provides stability, gaze control, spatial orientation; vestibular deficits → delayed head control and walking.

Question 9

What is the role of somatosensory input in head control?

Answer 9

At ~3 months, supports head/trunk alignment and reaching; requires calibration by vision.

Question 10

When does independent sitting typically develop?

Answer 10

Around 6–8 months.

Question 11

What are the 4 stages of independent sitting control?

Answer 11

1. No control (collapses). 2. Attempts but loses balance. 3. Upright but wobbly/leans forward. 4. Functional control with minimal sway.

Question 12

Which comes first: reactive or anticipatory balance?

Answer 12

Reactive balance; anticipatory control develops later with experience.

Question 13

How does trunk control for sitting develop?

Answer 13

Sequentially, segment by segment, not as a single block.

Question 14

How do newly sitting infants use vision?

Answer 14

They rely heavily on visual input; moving-room experiments disrupt their sitting. With practice, they integrate visual, vestibular, and somatosensory inputs like adults.