Prefrontal syndrome

Denotes involvement of the front precental gyrus , it was previously referred to as an organic psychosyndrome .

Prefrontal system

The prefrontal system is one of the largest cortical regions of the brain . It forms (together with the central region ) one of the two parts of the frontal lobe.

Function

• integration of information from different sources, planning, decision-making, new ideas (see below)
• integration of sensory perceptions (connection with the visual, auditory, olfactory, etc. cortex)
• integration of learning and memory (connecting with the limbic system)
• leading role on the regulation of the limmbic system (projection to the hypothalamus).
• various specifically human functions: abstract thinking, creativity, social relations, responsibility, etc.
• attention, perception, movement, temporal integration, emotions

Connections

• connections from the whole brain, mainly with the rostral thalamus ( mediodorsal nucleus of the thalamus)
• connections with mediodorsal nucleus of the thalamus:

• large cell part : to the orbital and medial parts of the prefrontal cortex
  • lesions: euphoria, hyperkinesia, inappropriate social behavior.
• small cell part : to the dorsolateral parts of the prefrontal cortex
  • lesions; apathetic-ablous syndrome, hypokinesia, congenitive disorders

Clinical signs

Clinical symptoms of prefrontal syndrome include:

• the so-called apathetic-abulous syndrome: (sometimes also referred to as amotivational syndrome),
  • apathy (numbness,surrender),
  • abulia (loss of will to do any activity).
• significant deterioration of memory in the implantable component,
• bradypsychism,
• the patient has no insight into his illness (anosognosia),
• undue euporia,
• moria (indecent jokes and vulgarisms),
• gatism (does not observe cleanlines, gives the impression of approval),
• ganserism (he tals about himself in the third person),
• gives approximate answers,
• puerilism (childish behaviour),
• amotional lability - apathy alternates wit bouts of rage.

The most serious manifestation of frontal lobe involvement is a comatose state.

Examination

During the examination, we objectify a number of reflexesreflecting prefrontal deliberation. Positivity of axial phenomena appears (nasolabial, mentolabial and sucking reflexes). A bilateral lesion of the prefrontal area leads to disorder of standing and walking, the so-called frontal gait Henner's crescendo retropulse – when the center of gravity is shifted backwards, the patient backs up with accelerating steps until he falls (impairment of the fronto-ponto-cerebellar pathway). When the frontal base is affected, hyposmia or anosmia from the olfactory pathway.

Links

related article

• Rolandic syndrome
• Frontal lobe syndrome
• Organic psychosyndrome

Použitá literatura

• SEIDL, Zdeněk – OBENBERGER, Jiří. Neurologie pro studium i praxi. 2. edition. Praha : Grada Publishing, 2004. ISBN 80-247-0623-7.

• BENEŠ, Jiří. Studijní materiály [online]. [cit. 2010-04-24]. <http://jirben.wz.cz>.