Pamela,
Proprioception refers to stimulation of the stretch sensitive nerve
endings in muscles, skin, and internal organs.  This is part of the way
the brain knows the position of various body parts in space, by the
degree of stretch of the fibers of various muscles.
        Some people have a decreased awareness or difficulty processing
proprioceptive information, this is a subset of sensory integrative
dysfunction.  They will have much more difficulty with 'grading' (the
smooth, gradual execution of a muscle contraction) of motions and 'motor
planning' (knowing how to move to achieve a specific goal without
thinking about it).  Proprioceptive input, properly done, can improve
these functions.  Occupational therapist with sensory integration
certification are the specialists in these issues.
        Your baby with the large tongue sounds like she also has a tongue
thrust or exaggerated tongue protrusion.  The difference between the two
is a matter of grading and cause:  exaggerated tongue protrusion occurs
in babies who are low tone or have respiratory difficulties.  The
movement is well graded...it flows easily, but he extension phase of
back (retraction)- front (protraction) movements is exaggerated so that
the tongue tip winds up between the gums or lips.  These children often
keep the tongue between the gums or lips to enlarge their airway.
Certainly they should be seen by a physician and if available, an
occupational or speech therapist who specializes in feeding.
        Tongue thrust is a more forceful, less well graded (controlled),
arrythmical protrusion of the tongue.  It is often seen in babies with
cerebral palsy.  It is made worse when the baby is extended at the hips
and shoulders.  Positioning the baby with the hips flexed and the arms
brought forward toward the midline of the body can decrease overall body
extension.  It is also recommended that the chin be slightly tucked, but
this must be done cautiously, because a child with respiratory problems
might be less able to maintain their airway as the larynx is brought
upward by the neck flexion.  (Just another reason why it is important to
be able to tell tongue thrust from exaggerated tongue protrusion, and to
try to determine the reason for these limiting movement patterns.)
        Other strategies that are useful for both problems include:
1. sublingual pressure - deep pressure to the base of the tongue under
the chin, right behind the jawbone during feedings.
2. work to normalize tone by rocking the baby through the spine before
feedings (hold baby on lap in sitting position, support neck and head,
rock baby back and forth gently to increase muscle tone.
3. try more upright positions at breast, so the baby is almost sitting.
remember to bring the baby's body forward at the hips, and the arms
forward to abduct the shoulder blades.  This is most useful for the
"arching" baby, who shows total body extension as well as tongue thrust
of exaggerated protrusion.
4. stimulate the lips immediately before feeding to increase their role
and decrease the role of the tongue - I like to gently tap all around
the outside of the lips with a fingertip, moving around the lip in a
circle to stimulate the entire orbicularis oris muscle that surrounds
the lips.

Good luck, these are challenging difficulties.
--
Catherine Watson Genna, IBCLC  New York City  mailto:[log in to unmask]