Neurological Benefits

Stress Reduction

Kangaroo care significantly decreases the amount of beta-endorphin (a stress indicator) in the blood (Mooncey et al., 1997) . Mooncey et al. (1997) showed a 74% geometric mean decrease in plasma beta-endorphin after kangaroo care. Beta-endorphin is synthesized by the anterior pituitary gland along with ACTH which induces cortisol secretion as a response to physiological stress (Guyton 1991).

Another study showed that salivary cortisol (yet another stress indicator) levels were lower in infants who received kangaroo care.

Adapted from Goldson 1999.

Following almost any type of stress cortisol release is greatly increased by the adrena lcortex, thus it is a good stress indicator (Guyton 1991)

State organization involves being able to transition in and out of different stages of sleep smoothly and into alertness (but not crying, which is the highest behavior state). Premature infants have a very difficult time transitioning from one stage of sleep to another and do not spend enough time in quiet sleep stages. Quiet sleep helps to protect the infants from environmental stimuli and fosters motor organization (Ludington-Hoe & Swinth 1996). Quiet sleep is also characterized by regular breathing patterns, so it leads to a decrease in apnea (Messemer et al. 1997). Crying is very bad for infants because it decreases lung capacity, increases intracranial pressure, reestablishes some fetal circulatory patterns and starts stress reactions within the body (Anderson 1999). Kangaroo care prevents crying, or at least severely limits crying in infants (Anderson 1999). In addition, it reduces active sleep and significantly increases quiet sleep.

Organization of Attention

Attention/interaction organization is demonstrated by the ability to process input from the environment. Even though infants younger than 40 weeks postconceptional age rarely exhibit attentive behaviors, Gale et. al (1993) showed that some infants older than 30 weeks gestational age have been observed gazing at their parent and trying to move their head to look at their parent after 10-15 minutes of Kangaroo Care (Ludington-Hoe and Swinth 1996).

Motor Organization

Motor organization is shown by control over movements and the absence of purposeless movements. Preterm infants have an especially hard time organizing their movements-loud noises or environmental changes cause them to flail their arms, extend their legs, heave their chests and move their heads. These movements use up oxygen and calories which need to be used for growth and development. Kangaroo care decreases purposeless movements by positioning them at a 60 degree angle, which also improves ventilation and makes breathing easier. In addition, being held between the breasts and hand limits motor activity. Kangaroo care induces relaxation, which improves breathing and also is a sign of motor organization (Ludington-Hoe and Swinth 1996).

Adapted from (Ludington-Hoe and Swinth 1996)

Self-Regulatory Organization

Self regulatory organization is seen in the ability to maintain self consoling behaviors, such as sucking, or hand to mouth maneuvers. Kangaroo care generally diminishes the need for self consoling behaviors, but at the same time it promotes self regulatory behaviors by on demand suckling and breastfeeding (Ludington-Hoe and Swinth 1996) . As shown below, Wahlberg, Affonso, & Persson (1992) showed that more kangaroo care infants breastfeed at discharge and Bier et al. (1995) showed that more kangaroo care infants continue breastfeeding at discharge than control infants. Breastfeeding is important because it represents the development of sucking, which is sometimes not present at birth for premature infants. Breastfeeding also is important because it is a consoling behavior for the infant, which leads to relaxation (Ludington-Hoe and Swinth 1996). In addition, stimulation of the infants sensory nerves in the oral mucosa may lead to a vagaly mediated hormone release in the gut, which could aid in nutrient absorption and lead to faster weight gain (Anderson 1999).

Both Figures adapted from (Ludington-Hoe and Swinth 1996)