Frontal brain syndrome

Classification according to ICD-10
F07.0	Organic personality disorder
F07.2	Organic psychosyndrome after head trauma
F07.8	Other organic personality and behavioral disorders due to an illness, damage or dysfunction of the brain
ICD-10 online (WHO version 2019)

Frontal lobe syndrome is the collective name for the symptom complex that is caused by damage to the anterior parts of the frontal lobe .

There are similarities to “dysexecutive syndrome” , which refers to impaired executive functions . Both “dysexecutive syndrome” and “frontal brain syndrome” are, however, controversial as terms in the professional world.

Equating them should be avoided at all costs, as both terms denote different things. The term "dysexecutive syndrome" aims at disorders of various cognitive functions with clearly different symptoms from patient to patient - while the term "frontal brain syndrome" indicates the anatomical localization of damage. However, if the frontal lobe is damaged, executive functions do not always have to be affected. Conversely, the executive functions are not only disturbed if there is damage to the frontal lobe, since other areas of the brain (e.g. the thalamus) must also function properly for the executive functions. A prominent patient with frontal brain syndrome was Phineas Gage , who suffered a lesion in the orbitofrontal and prefrontal cortex in 1848 and survived them.

In general, this part of the brain, also known as the prefrontal cortex, is assigned an analysis and monitoring function. This is why the term “supervisory attentional system” (SAS) was introduced for him. There is a dense network to many other parts of the brain. In this way, a wide variety of information can be analyzed, evaluated, “calculated” and the results sent back - similar to the central processor (CPU) of a computer. Due to the numerous prefrontal connections (" projections ") to other brain structures, lesions in other brain areas can also lead to a dysexecutive syndrome, e. B. thalamus , cortical or subcortical limbic structures , basal ganglia .

Areas of the prefrontal cortex

Location of the orbitofrontal and dorsolateral areas in the human prefrontal cortex (side view).

There are two general areas of the prefrontal cortex (PFC):

Dorsolateral prefrontal cortex (DLPFC): This is where mainly cognitive functions are located, e.g. B. problem-solving thinking, planning ahead or purposeful action
Orbitofrontal Cortex (OFC): This part of the brain is associated with personality traits and the ability to regulate emotions .

In general, the PFC has the function of adapting human behavior flexibly and appropriately to new demands in life. It is also of outstanding importance when it comes to the "temporal organization of behavior".

Cognitive disorders after damage to the dorsolateral prefrontal cortex

The Supervisory Attentional System (SAS) is no longer able to flexibly adapt human actions to new situations (cognitive flexibility). Problem-solving thinking and forward-looking action planning are z. T. massively disturbed. Irrelevant (environmental) stimuli can no longer be distinguished from relevant ones. There is no longer a sufficient analysis. In contrast, routine actions usually do not show any problems. People with damage to the frontal lobe are mostly unremarkable here: z. B. Shopping for everyday things, breakfast or dinner, attending doctor's appointments, etc.

The following cognitive disorders can occur as part of a dysexecutive syndrome and can be recorded with different tests:

Insufficient problem analysis
Insufficient extraction of relevant features
Insufficient production of ideas (loss of divergent thinking and ingenuity)
Reduced verbal fluency and reduction in "spontaneous speech"
Sticking to (irrelevant) details
Insufficient adaptability and tendency to perseveration
Insufficient compliance with rules and rule violations (also in social behavior)
Use of routine activities that are irrelevant to planning
Reduced plausibility checks
No systematic troubleshooting
Alternative plans are rarely developed
The concept that guides the action is lost
Difficulty observing several pieces of information at the same time ( working memory )
No multi-tasking possible
Consequences of action are not foreseen
No learning from mistakes
Careless and hasty action (increased impulsiveness )
Give up quickly when there are barriers to action (reduced persistence and willpower )
Knowledge can no longer be translated into effective actions ("knowing-doing-dissociation")

Possible behavioral disorders after damage to the orbitofrontal cortex

Damage to the orbitofrontal cortex or associated brain areas can lead to various behavioral problems. One also speaks of neuropsychiatric disorders . The specialist literature distinguishes between inhibitory and disinhibitory symptoms. These in turn can be described on different levels. The constellation of symptoms that occurs depends on the extent and type of frontal brain damage. A rough subdivision is the distinction between an upper and a lower frontal brain syndrome, whereby the upper frontal brain syndrome is essentially characterized by a lack of drive (inhibitory), while the lower frontal brain syndrome is mainly characterized by disorders of affect and the ability to criticize (disinhibitory).

Depressive-inhibitory symptom complex ("pseudodepression")

Motorized

Motor slowdown
Speech impoverishment

Sensory

Lack of responsiveness to environmental stimuli
Apathy (indifference)

Emotionally Affective

Depressed mood
Low self esteem
Self-denial
Numbness and indifference

behavior

Appetite and weight loss
Loss of energy and interest
Loss of initiative and sexual desire
Neglect of outward appearance
Social withdrawal

Cognitive

Abulie ( incapacity to make decisions and make decisions)

"Pseudo dementia "

Attention and concentration disorders

Biocyclic

sleep disorders
fatigue

Disinhibitory symptom complex ("pseudopsychopathy")