The frontal lobes are the largest and most likely the complex structure in the brain. Among other functions, it allows the expression of personality and language, the planning and sequencing of desired movements or actions as well as inhibition of unwanted or undesirable ones. Given the regional distribution of function, lesions or dysfunction in the frontal lobes may lead to a wide variety of presentations, including weakness, aphasia, perseveration, disinhibition, personality changes and acquired sociopathy. Besides trauma, tumours, infections and toxins, abnormal disorders of tau and ubiquitin proteins may lead to neurodegenerative diseases that predominantly affect the frontal lobes. These so‐called frontotemporal dementias or frontotemporal lobar degenerations have become one of the most active and exciting field of research.
Frontal lobes mediate various processes, ranging from simple motor function to personality and inhibition.
The frontal lobes can be divided in different areas, which can be associated with different functions.
Multiple pathologic processes can affect the frontal lobes.
Disorders affecting the frontal lobes can present in various ways ranging from weakness to personality changes.
Some of these changes might be undetectable at the bedside examination and might require thorough neuropsychological evaluation.
Keywords: frontal lobes; personality changes; executive dysfunction; Broca's aphasia; frontotemporal dementia