The separate and combined effects of GSR biofeedback and delayed auditory feedback on stuttering: A preliminary study

by in Treon, Washington

State Univksity

Washington

State University

upon stuttering dyse stutterers who were

e the subjects n it is accomplished,

in this

functions

compared to no DAF conditions. gnificantly fewer blocks I than under DAF alone. g these findings overall, uency facilitating effect is additive i.e., greater

The biofeedback process involves immediate presentation of an interpretable and amplified physiological par’ameter measurement e.g., heart rate, GSR, EEG, to an individual for self regulation. Such biofeedback process is employed in tl.e following experiment. Specifically, stuttering dysfluency is studiecl as a function of: (1) no biofeedback; neither amplified delayed auditory feedback (DAF), nor galvanic skin response biofeedback (GSR BF), (2) only DAF, (3) only attempted galvanic skin response biofeedback low wave amplitude self regulation (GSR LW), and (411combined DAF and GSR LW. 3

it was ccur under low w

!i,19Sl),

Four experimenters met WI 28 one hour sessions over

w’o male stutt

to control

for sequence-of-

sentation each with its own Latin Square Table, two for each of the fnur experimer.‘.ers, were used to control for order-of-condition effects. A twti minute “relaxation” time was employed between each five minute condition to further control for order-of-condition effects. The iss~ of possible experkmenter bias in judging stuttering blocks was discussed prior to the experiment and a conscious effort was made throughout to maintain consistent criteria in judging

‘For a brief review of the use ?f GSR, bwt not GSR BF, in stuttering research and therapy, the reader is referred to Vcln Riper (1971, pp. 175, 311).

4

locks irre of the ccurred. , no in judge reliability measures mation concerning experimental

hypotheses,

consultation

speech and hearing clinic setting.

room in a university

ition in which they ere used or inter-

d to rest his right The subject was monologues about plans, current happenings, or past events. He was instructed to maintain the same convers~tioflal rate during each monologue and not to slow down ven &ring the DA here was no other attempt to control for or measure speaking rate changes between ntal conditions. The DAF headphones were then fitted subject’s ears and remained in place during each monologue whether or not DAF was being employed. Although the GSR ed on during each of the four experimental conaside and not to look at ject was instructed to t conditions. Yn this way, uring the two no GSR o sets of four conditions the subject completed eight condition each, each separated by a two minute period of relative quiet in a one hour session. Using a small hand co nter, the experimenter recorded each stuttering block judged to have occurred during each condition. A t-test for related measures was used in all of the stabistical analysis of these data. In this experiment, an “out” is a GSR amplitude excursion that goes beyond (outside of) the low wave amplitude limits defined on the graphing paper. Counting in this way, the

5

No OAF

TABLE 2. Numbor of Itutoring blocks and “outs” wtder (A) conditions, and (B) combined GSR LW vews combi

A

Combined OAF

Total

Combined No OAF

blks

out

bib

ouh

1476

3926

3w9

4460

6

blocks n data

“outs” scparat

combin accomp

LW versus combined no nd not accomplished com-

Not Accomplished

No GSR SF

GSR LW --

1

9

1154 352

a

total

1332

1

1175

2560

blks

outs

blks

outs

1100

1712

1113

1717

76

379

60

450

1176

2091

1173

2167

esults suggest that G oderately but signifi time i.e., is not a short effect does not noticeab ing, it would be of interterm distraction device. I est to examine the possible relationship between other types of biofeedback self regulation, especially EMG and EEG, and stutterysfluency. Such a study could be either in relation to or conjunction with either GSR LW or DAF, or both.

One speculative

~~ter~retatio~

of the ~unctic~a~ relationship

be-

ied in this way, GS

If GSR LW, through anxiety and tension reduction, acts upon certain secondary or socially acquired aspects of stuttering, it can be speculated that DAF acts up.on certain primary or core aspects of stuttering by somehow temporarily reintegrating the partially disintegrative coarticuiation process that primary stuttering may considered to be. The word “somehow” in the context of the preceding sentence covers, of course, a host of “sins” of explanatory omission. But viewed in this way, core stuttering dysfluency is understood as ?I miscoarticulation dysfunction; a kind of quantitative articulation dysfunction in perceptual articulatory time as opposed to qualitative articulation dysfunction in perceptual articulatory space. Thus, as an intermittent coarticulative disintegration, core stuttering is, broadly, a unitary dysfunction. But the specific sources and dynamics of this disintegration within the speech sound perception-feedback-production coarticulation process are not at all clearEy defined, much less understood. It may be that the “somehow” of this possible reintegrative effect of DAF upon stuttering dysfluency will come to be more exactly defined as normal coarticulation process is r -Ire comprehensively understood, In any case, if OAF does act upon core stuttering dys!luency, its pronounced and sustained fluency facilitating effect suggest that

8

ore what one intermittent

g i.e., speaking in ve disintegration.

co

contributions

, Conversational rate control thera and .Hearing Research, 34,245-250 (

Row (1970). Soderberg, 6. A., Delayed auditory feedback and stuttering. Journal of eech and Hearing Disabilities, 33, X9-267 ( 1 . D., Anxiety and Behavior, I’_w and Kaplan, B. E., Galvanic skin response: voluntary control &nalization. Journal of Psychosomatic Research, 10. 345-353 ., The Nature of St&taring,

Englitwoo$ Cliffs: Prentice-Hall

, The Practice of Behavior Therapy,

9

ew York: Pergamon Press