sentience vs modality

sentience and modality both are nouns.

Word	Noun	Adjective	Verb	Adverb
sentience	Yes	No	No	No
modality	Yes	No	No	No

As nouns, modality is a hyponym of sentience; that is, modality is a word with a more specific, narrower meaning than sentience:

Other hyponyms of sentience include sense modality, sensory system, sensibility, sensitiveness, sensitivity.

sentience (noun)	modality (noun)
the readiness to perceive sensations; elementary or undifferentiated consciousness	a method of therapy that involves physical or electrical therapeutic treatment
the faculty through which the external world is apprehended	a particular sense
state of elementary or undifferentiated consciousness	a classification of propositions on the basis of whether they claim necessity or possibility or impossibility
	verb inflections that express how the action or state is conceived by the speaker