Prefrontal syndrome
Denotes involvement of the front precental gyrus , it was previously referred to as an organic psychosyndrome .
Prefrontal system
náhled|Prefrontální kůra a její části zvýrazněné odstíny modré barvy. 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
- large cell part : to the orbital and medial parts of the prefrontal cortex
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 [1] 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.
