and responded to in seconds. The specific inquiry into subvocalization may be minimal right now but there remains much to investigate in regard to the modular mind. Associated brain structures and processes The brain mechanics of subvocalization are still not well understood. It is safe to say that more than one part of the brain is used, and that no single test can reveal all the relevant processes. Studies often use event-related potentials; brief changes in an EEG (electroencephalography) to show brain activation, or fMRIs. Subvocalization is related to inner speech; when inner speech is used, there is bilateral activation in predominantly the left frontal lobe. This activation could suggest that the frontal lobes may be involved in motor planning for speech output. Subvocal rehearsal is controlled by top-down processing; conceptually driven, it relies on information already in memory. There is evidence for significant left hemisphere activation in the inferior and middle frontal gyri and inferior parietal gyrus during subvocal rehearsal. Broca's area has also been found to have activation in other studies exploring subvocal rehearsal. Silent speech-reading and silent counting are also examined when experimenters look at subvocalization. These tasks show activation in the frontal cortices, hippocampus and the thalamus for silent counting. Silent-reading activates similar areas of the auditory cortex that are involved in listening. Finally, the phonological loop; proposed by Baddeley and Hitch as “being responsible for temporary storage of speech-like information” is an active subvocal rehearsal mechanism, activation originating mostly in the left hemispheric speech areas: Broca's, lateral and medial premotor cortices and the cerebellum. Role of subvocalization in memory processes The phonological loop and rehearsal The ability to store verbal material in working memory, and the storage of verbal material in short-term memory relies on a phonological loop. This loop, proposed by Baddeley and Hitch, represents a system that is composed of a short-term store in which memory is represented phonologically, and a rehearsal process. This rehearsal preserves and refreshes the material by re-enacting it and re-presenting it to short-term storage, and subvocalization is a major component of this rehearsal. The phonological loop system features an interaction between subvocal rehearsal and specific storage for phonological material. The phonological loop contributes to the study of the role of subvocalization and the inner voice in auditory imagery. Subvocalization and the phonological loop interact in a non-dependent manner demonstrated by their differential requirements on different tasks. The role