We are currently testing out the best way to do fMRI studies in patients with epilepsy. It would great if you could recommend some of the established tests for auditory comprehension paradigm.
I would recommend to you an article from Crinion & Price entitled "Right anterior superior temporal activation predicts auditory sentence comprehension following aphasic stroke", which was published in Brain in 2005 (128, 2858–2871). The authors used an auditory sentence comprehension task within the settings of an fMRI study in aphasic patients and in healthy controls.
Common tests for speech comprehension are too easy for patients with normal hearing, regardless of the disorder in most cases. Probably you should look tests that tax the auditory system such as competing speech tests in noise such as the HINT, QuickSin, or Synthetic Sentence Identification (Ipsilateral Competing Message) or dichotic test such as the the Synthetic Sentence Identification (contralateral competing messages) and possibly the Dichotic Sentence Identification test or even Dichotic Digits. Auditec of Saint Louis ( www.auditec.com) has pre-recorded tests of many types you may want to review. I would think that a better representation of activity would be preferred when the auditory system is more engaged with more complex processing.
Thanks Bernard and Dennis. Truly appreciate the information that you both shared.
I think it depends what you are using the task for. Are you looking for something that functions as a functional localizer from which you can create regions of interest for other more specific effects? Or are you trying to identify specific comprehension components? That may help you narrow the types of tasks that are appropriate for your purposes.
I am assuming you're looking to lateralize language for presurgical planning? One simple test, that has been fairly successful includes flashing a description of an object for the patient to read. His/her response will be to silently name the object to themselves while in the MRI. The control portion of the test could be nearly anything, but usually staring at a cross on the screen of their goggles works well. A good description of the task can be found in "Language dominance in partial epilepsy patients identified with an fMRI reading task" Neurology (2002) 59, 256-265. Hope this helps!
Alexander Stevens: We are actually looking for a task that captures the speech perception/ production which would also help to lateralize to the left posterior superior temporal gyrus.
Caleb Pearson: We are currently in the midst of developing appropriate measure that would best asess/localize language functions in TLE patients, and yes it is supposed to be a routine protocol for presurgical planning.
Dr. Veeramuthu,
If that's the case, the task I've described should work fine. One thing to keep in mind is that comprehension tasks in particular (compared to language production tasks) tend to show more bilateral involvement on fMRI studies compared to Wada studies or intra/extraoperative mapping using electrocortical stimulation. This has led some to believe that fMRI leads to a greater chance of errantly labeling a patient as having bilateral language (although it may just be that fMRI is more sensitive to the subtle involvement of the right hemisphere in language compared to more quick and dirty applications like the Wada test).
All the best,
CP
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