We begin by noting that, in addition to the more or less established trends of cognitive modelling and neurolinguistic or behavioural experimentation, a more recent orientation in research on interpreting (IR) as a complex cognitive process is functional neuroimaging. We then describe current brain imaging methods — electroencephalography, magnetoencephalography, positron emission tomography, functional magnetic resonance imaging, and near-infrared spectroscopy — and provide selected examples of their use in language processing and interpreting research, accompanied with brief evaluations of their applicability for IR. In spite of limitations related to invasiveness, temporal resolution, and experimental design, positron emission tomography (PET) is potentially the strongest tool for investigations of the neural substrates of ongoing interpreting performance. Finally, we describe what we believe is the first published study of speech shadowing and professional simultaneous interpreting using PET. Shadowing of the non-dominant language produces more extensive activations in the temporal cortex and motor regions than shadowing of the dominant language, which suggests that even in the simultaneous repetition task, the less automatized language recruits more neural resources. Simultaneous interpreting, whether into the dominant or into the non-dominant language, predominantly activates left-hemispheric structures. Activation patterns are, however, clearly modulated by the direction of interpreting, with more extensive activation during interpreting into the non-dominant language.
Functional neuroimaging of normal human sleep by positron emission tomography