Are there EEG waveforms (blips?) that can be used to mark the onset and offset of words or sentences produced with expanded inner speech?

One possibility to define the on- and offset of long utterances is - to additionally monitor  respiration and measure exhalation intervals. It may not be 100% precise, but especially for long utterances a good marker, see:

Conrad, B., Schönle, P. (1979) Speech and respiration. Archiv für Psychiatrie und Nervenkrankheiten, 226:251-268.

Apart from this, I believe it makes sense what you say. There are also algorithms around looking at EEG speech artefact removal for overt speech production. The artefact is clearly a marker of the onset.

Best Susanne

Hi Ron......EEG changes related to single events of 'inner speech' may be difficult to resolve, dependent on brain network and localization, S/N, and motor artifacts associated with overt speech production.   I am not familiar with the 'inner speech' literature.  A starting point using EEG might involve dense array 256-chan nets and a scheme in which test participants are cued to generate 'inner speech' and signal average many such trials, (perhaps N=100), in an attempt to map the spatiotemporal features of electrocortical dynamics triggered to the inner speech initiation cue.  Maybe this has been done.     S

Hi Ron, Nice to see a familiar face here!  My comments may not be particularly relevant because my conception and typical use of the term "inner speech" is related to Vygotsky's use of the term.   If that is not the way it is being used....then please excuse the first set of comments... if this IS how it is being used, then I think you can do such measurements but with a large caveat....In the Vygotskean use, inner speech is far more collapsed in terms of meaning and conceptualization. That is, his conception of "inner speech" (and even words) are quite different than what we tend to use in that it (and they...words) are really more abstract conceptualizations.....so even if they were processed equally to "externalized speech" the semantic/conceptual load would be far more extensive.  If you are NOT using the term in a Vygotskean sense, perhaps somewhere that differentiation might be spelled out so people who are non-speech scientist may not be confused.

The second comment (for what it is worth) is that it appears that you are employing the Derivational Theory of Complexity to look at this processing....It seems to me that several years ago some linguists joined with some neo-behaviorists (an odd combination of scholars!) to criticize the DTC because it is based more on linear processing than parallel distributive processing (a favorite, of course of Neo-behaviorists in cognitive science).  As you are aware, I am not a speech scientist or a psycholinguist ....more clinical and applied .. so you may have more information on this and my comments not of interest....but I thought I would mention them...I would like to see the study when you complete and publish it.

Jack

Thanks to you three for interesting suggestions.

There are two things that come to my mind.  First, one should be able to see a spike at the onset and a decay at the termination of speech if you are tapping the signals at C3, C4. or F3, F4.  The planning of opening the mouth and the corresponding signal should be evident at F3, F4.  Secondly, one may even get an EMG signal due to the muscle movement.  Strictly speaking, it is an artifact.  However, it may even do the job for your experiments.  Let me know your thoughts.