Frontal Lobe Pathologies
Action-Intentional disorders Frontal lobe damage may lead to a wide range of disorders in connection with intentional action, such as (Kreutzer 2011, p. 26):
• Abulia: lack of motivation, will, drive, and initiative
- • Akinesis: inability to initiate movement
- • Hypokinesis: diminished ability to move
- • Motor impersistence: inability to sustain motor action
- • Motor preservation: repetition of motor action after task completion
Given that the frontal lobes carry out executive functions, these disorders make
Broca’s aphasia: language production impairment Broca’s area lies along the lateral fissure and is critical for speech production. Damage here leads to ungrammatical, cryptic language expression, both in speech and in writing. However, language comprehension may remain unaffected, as it is associated with Wernicke’s area in the temporal lobe.
The case of railroad worker Phineas Gage (1823-1860) Gage suffered prefrontal cortex damage in 1848 when tamping dynamite in rock. A spark ignited the dynamite, sending his 13-lb tamping iron flying up on the inside of his left chin bone, onward through his prefrontal cortex, and exiting at the top of his skull just across the midline, on the opposite hemisphere. According to commentators, his personality changed from pleasant to impulsive and brutish. But he recovered significantly over time, illustrating how plastic the brain can be (Macmillan 2000).