In the present corpus, totalling 21 minutes, the female participant, here to be referred as participant 1 (p 1), held the floor 33 times and the male participant, participant 2 (p 2), held the floor 32 times. There were thus 64 exchanges of turn, including four simultaneous turns resulting from turn-taking attempts. The average time of one turn was about 19 seconds, but the enormous variability in length of a speaker turn has to be mentioned. Turns ranged from a couple of words to several thousands in length. One exceeded two minutes in duration.
In the following there are 15 screenshots presented, some of them arranged as sequences taken from one turn-taking situation.
The first sequence consists of pictures 1 - 5. The sequence was chosen as a typical example of gestural behaviour in the course of a change of turns.
As picture
1 shows, p1 holds the floor. She gazes at p2, but
doesn´t make use of any gestures. P2, on the other hand,
is sitting still, holding eye contact to p1. Thus,
picture 1 stands for a typical part of a smooth
interaction.
In picture 2 some things
have changed. P1 still holds the floor with eye contact
to p2. However, her posture has changed. Her body is a
bit leaned back and her arms are crossed. This may be
seen as her reaction to p2´s gestural behaviour who has
set upright and started a self-adaptor (e.g. fumbling
with a butto of his shirt) to indicate that he is willing
to take the turn.
Picture
3 shows the next step of the turn-taking process.
While p2 continues to display his self-adaptor as a
turn-requesting cue, p1 gives an open hand gesture to
indicate that she is ready to leave the floor to p2. Eye
contact is still lasting.
Picture
4 exactly displays the moment of turn-taking. P1´s
posture has nearely remained the same and she is gazing
at p2 expecting his turn. P2 has turned away his head,
concentrating on starting his turn. The start of his turn
is accompanied by another self-adaptor reminding of
rubbing one´s hands.
Finally, p2 has taken the floor (picture
5). He typically uses a hand gesture to illustrate
his thoughts. P1´s posture has remained the same. She is
concentratedly listening to p2. Eye contact has been
reestablished.
Picture
6 shows a very strong gestural behaviour in the sense
of turn- requesting. P2 holds the floor, using hand and
arm gestures and is gazing at p1. P1 seems to be strongly
affected by P2´s words, because she similarly produces a
combination of gestures. Firstly, she shifts her posture
by leaning forward her upper body and, seconcdly, she
shows a broad smile. She has interrupted eye contact. P2
reacts and leaves the floor to p1.
P1 has
held the floor for a longer time and p2 has shown some
turn- requesting cues, for example some activities with
his hands (picture 7). Obviously p1 is not willing
to finish her turn, showing this by using an open hand
gesture and maintaining eye contact.
As p2
continues his turn-requesting activities, p1 passes over
to another hand gesture (picture 8). She now uses
her hands to enumerate important points of her thoughts,
while having interrupted eye contact. So, her hand
gesture, in combination with the interrupted eye contact,
underlines that she is not willing to leave the floor to
p2.
As a
result of that turn-maintaining behaviour p2 has stopped
his gestural activities and is sitting still. P1 has
re-established eye contact and continues her turn (picture
9).
As to
be seen in picture 10, p2 holds the floor
displaying a broad arm and hand gesture and is gazing at
p1. P1 on the other hand has turned away her head and
shows an angry face. Her left arm produces a very sharp
gesture that really cuts off p2´s flow of speech.
The
result of that combined arm gesture and facial expression
is that p2 has stopped his speech act and his gestures (picture
11). He is sitting still and gazing at p1 who has now
taken the floor. She continues showing an angry face, but
has reestablished eye contact.
Pictures 12 and 13 give examples of back-channel cues.
In picture
12 p2 is speaking. He displays no gestures and his
gaze at p1 includes the question whether she is willing
to take over the turn. However, p1 shows some
back-channel cues, laying back her head and rubbing her
chin. Moreover, she interrupts eye contact to p2. He
reacts to these back-channel cues and continues speaking.
Another
back-channel situation can be observed in picture 13.
This time p1 holds the floor, gazing at p2. As a
back-channel cue he completely shifts his posture by
turning away from p1 and looking down on the ground. In
addition to that he nods and gives a verbal agreement to
p1. As a reaction to these very strong back-channel cues
p1 continues speaking.
The last sequence (pictures 14
and 15) shows the situation of simultaneous speaking,
a situation that should be prevented by a functioning
turn-taking mechanism.
As picture 14
reveals, both participants are speaking, both of them
displaying hand gestures. 
P2´s hand gesture seems to be the
more stressed one, because he is the one to keep the
floor. His hand gesture is reinforced by a light shift of
posture. P1 on the other hand, gives up the floor,
demonstrating that by leaning back and shrugging her
shoulders. So, she obviously shows that she gives up the
floor.