This is a sketch pad for some observations on blinking (Short video of blinks). My primary interest lies in interpreting and understanding blinks as they occur in live communication. Little is known about the role of such blinks in communication. We know quite a bit about the physiology of blinks, some things about the relationship of blinks to “inner” activity such as concentrating, word finding, etc. But little about the role of blinking in naturalistic communication.

Blinking Literature

An unordered and growing collection of articles on references to scholarly publications on blinking is available from my CiteULike collection.

Here are some experimental findings of mine. The manuscript is currently under (re-)review.

I also like the discussion of blinking from an animator’s point of view (part 1, part 2, part 3), courtesy of SynchroLux.

Examples of blinks

I am slowly assembling a collection of illustrative examples of blinks. Most of these are from the wonderful IFA Dialog Corpus, which records lots of dyads, known to each other, conversing face to face. A camera sits behind each participant, allowing excellent blink registration.

Types of blinks

There are a few blink taxonomies out there, none of them terrifically authoritative, and each serving different purposes. One conventional three-way distinction is between blinks that are spontaneous, voluntary, and reflex. The latter have their origin in excitation of the trigeminal nerve. Within the category of spontaneous blinks, one may identify complete and incomplete blinks.

Blinks are often tied to shift of gaze (as described in Evinger et al., 1994). For large changes of gaze direction, head movement, eye movement, and blinking are closely linked.

I have found all the above distinctions to be of relatively little use in studying communicative blinking. I do not yet have sufficient quantitative data to form the basis of a strict ontology, but I tentatively observe the following:

  • In face to face conversation, blinks are very likely when gaze shifts to or away from the partner. They are much less likely for gaze shifts that do not start or end with eye-to-eye contact.
  • The most common kind of spontaneous blink is made during eye-to-eye contact. The frequency with which these occur depends greatly on whether the other person is looking, and at whether the blinker is speaking or not (far more blinking occurs when listening than when speaking).
  • These blinks are distinct from blinks occasioned by lexical access difficulties, or syntactic complexity. These tend rather to occur in flurries, during which the direction of gaze moves from the partner.
  • Incomplete blinks are quite common, and not distinguished meaningfully from complete blinks.
  • When one person has the floor, the stream of backchannelling utterances of the other may entrain their blink production, so that “yes” or “uh huh” and blinks co-occur. This happens often, but is by no means obligatory.
  • Some blinks have very clear communicative intent: encouraging or supporting the speaker.

Some final thoughts from Michael Caine: