Broca's+Area

Broca's speech are is located in the general vicinity of the posterior- inferior region of the left frontal area (i.e. third frontal convolution).

Broca's speech area is a final converging destination point through which thought and other impluses come to receive their final sequential (syntactical, grammatical) inprint so as to become organized and expressed as temporally ordered motoric articulations; i.e. speech. Verbal communication, the writing of words (via transmission to Exner's area), and the expression of thought in linguistic form is made possible via Broca's area which programs the adjacent oral-laryngeal musculature as represented within the adjacent primary motor areas; and which transmits to Exner's writing area so that words may be written. Primary Functions:

portions of areas 45, 6, 4, and all of area 44
 * Broadman's Areas**

auditory, visual, somesthetic areas -Inferior parietal lobule -Wernicke's area via arcuate fasciculus (which also links these areas to the amygdala). -Anterior cingulate -Brainstem -Periaqueductal gray which subserves vocalization.
 * Connected From**


 * Connected To**

Speech arrest and can alter the ability to write and/or perform various oral-facial movements.
 * Electrical Stimulation**

-Loses the capacity to produce fluent speech. -Output becomes extremely labored, sparse, and difficult, and may be unable to say even single words, such as "yes" or "no". -Often, immediately following a large stroke patients are almost completely mute and suffer a paralysis of the upper right extremity as well as right facial weakness (since these areas are neuronally represented in the immediately adjacent area 4). Patients are also unable to write, read out loud or repeat simple words. Interestingly, it has been repeatedly noted that almost immediately following stroke some patients will announce "I can't talk", and then lapse into frustrated partial mutism.
 * Injury/Damage**

With less severe forms of Broca's aphasia: -Speech remains labored -Agrammatical, fragmented -Extremely limited to stereotyped phrases ("yes", "no", "shit", "fine") & contaminated with syntactic and paraphasic errors i.e. "rutton" for button -Writing remains severely effected, as are oral reading and repetition. -Mild difficulties with verbal perception and comprehension including the ability to follow 3-step commands -Commands to purse or smack the lips, lick, suck, or blow are often, but not always, poorly executed (bucal-facial apraxia) -Non-speech oral movements are seldom significantly effected

Mild damage: -Severe confrontive naming and word finding difficulties (anomia) -Possible right facial, hand, and arm weakness -Speech is often characterized by long pauses, misnaming, paraphasic disturbances and articulatory abnormalities -Stammering and the omission of words

** Notes: ** Disturbances involving grammar and syntax, and reductions in vocabulary and word fluency in both speech and writing have been observed with frontal lesions sparing Broca's area. In word fluency tests, however, simple verbal generation (e.g. all words starting with L) is usually more severely impaired than semantic naming, e.g. all animals which live in the jungle--which is presumably a function of semantic processing being more dependent on posterior language areas.

Left frontal lobe becomes activated during inner speech and subvocal articulation. The left frontal lobe also becomes highly active when reading concrete and abstract words, and when engaged in semantic decision making tasks. Moreover, activation increases as word length increases and in response to long and umfamiliar words.