Summary Chapter 8 + lecture
notes
Frontotemporal dementa
Prevalence of FTD is much lower than that of AD. It is more prominent in men than in women.
Research has reported a family incidence of 50%, implying a strong genetc component. The course
of disease is much more rapid than that for AD, and mortality is signifcantly increased if the frontal
type of FTD is combined with amyotrophic lateral sclerosis. Three clinical subtypes: frontal variant,
temporal variant (semantc dementa), and progressive non-fuent aphasia variant.
FTD is linked to chromosome 17 and is characterized by dementa and Parkinsonism. They are
classifed as patents with Pickss disease. Neuropathology is quite specifc, no overlap with AD or VaD.
Frontal variant
Severe early atrophy in frontal regions and later also in lateral anterior temporal and parietal regions.
Early stage atrophy in frontal and prefrontal cortex and hippocampus. Some white mater lesions
may be present. Reduced metabolism is seen in right medial PFC, orbitoprefrontal cortex and ACC.
Glucose metabolism declines in frontal cortex due to defcit in serotonergic neurotransmiter system.
Furthermore we see an impairment in the nigrostriatal dopamine system hypoperfusion in lef
superior frontal cortex and reduced vascularizaton ACC. Not all brain stem areas are afected in FTD,
but the fnal cortcal area of the ARAS, the frontal cortex, is afected. In the frontal variant, the
frontostriatal circuit is also strongly afected reduced vascularizaton in ACC. Hippocampus shows
reduced metabolism frontohippocampal circuit afected. Dysfuncton of ACC and hippocampus
expresses itself in disinhibited behavior, typical for a patent with frontal variant of FTD. Clinical
manifestaton of strictly prefrontal dysfuncton would result in apathy.
Frontal variant of FTD is also primarily characterized by cognitve, behavioral and personality
disturbances that are related to EF. Impairments of episodic memory do not occur untl later in the
disease progress. Behavioral disturbances characteristc of frontal FTD are: disinhibited behavior,
reduced impulse control, ant-social behavior, stereotypical behavior, compulsiveness, Klüver-Bucy
syndrome and apathy (may be due to impairment in voliton). Their regulatng capacites decline
progressively, making them very dependent on their environment.
Voliton, purposive acton / self-regulaton, and efectve performance (all EF) are impaired in the
frontal variant of FTD. Memory decline does not occur in early stages, making FTD patents easily
distnguishable from AD and amnestc MCI patents. Later; anterograde amnesia, recogniton beter
than actve recall and impairment in remote memory (frontal associaton areas). Intact functons:
visuospatal abilites, naming, word-picture matching, performance of semantc tasks, recent memory
and orientaton.
Temporal variant
Temporal variant occurs more rarely than frontal variant. Atrophy mainly in ventromedial PFC and
hippocampus. Neuronal loss found in anterior and inferior temporal lobes, partcularly in the lef
hemisphere (parahippocampal gyrus and fusiform gyrus). Relaton between ARAS and temporal FTD
not examined. Brain areas that play a role in specifc functonal circuits and that are afected include:
PFC, hippocampus, parahippocampal gyrus. This results mainly in dysfuncton of frontohippocampal
and hippoparietal circuits. Atrophy of hippocampus is not a consistent fnding though.
Difering symptomatology seen in lef and right hemisphere afected. Those with lef hemisphere
afected show decline in semantc knowledge (anomia, word fnding difcultes, and repettve
speech), and tend to be socially pleasant. Those with right hemisphere afected also show aphasia,
but more ofen also behavioral and personality problems in inital stages. Verbal and physical threats
are ofen expressed by these patents. Depression occurs in both groups, but nature of depression
notes
Frontotemporal dementa
Prevalence of FTD is much lower than that of AD. It is more prominent in men than in women.
Research has reported a family incidence of 50%, implying a strong genetc component. The course
of disease is much more rapid than that for AD, and mortality is signifcantly increased if the frontal
type of FTD is combined with amyotrophic lateral sclerosis. Three clinical subtypes: frontal variant,
temporal variant (semantc dementa), and progressive non-fuent aphasia variant.
FTD is linked to chromosome 17 and is characterized by dementa and Parkinsonism. They are
classifed as patents with Pickss disease. Neuropathology is quite specifc, no overlap with AD or VaD.
Frontal variant
Severe early atrophy in frontal regions and later also in lateral anterior temporal and parietal regions.
Early stage atrophy in frontal and prefrontal cortex and hippocampus. Some white mater lesions
may be present. Reduced metabolism is seen in right medial PFC, orbitoprefrontal cortex and ACC.
Glucose metabolism declines in frontal cortex due to defcit in serotonergic neurotransmiter system.
Furthermore we see an impairment in the nigrostriatal dopamine system hypoperfusion in lef
superior frontal cortex and reduced vascularizaton ACC. Not all brain stem areas are afected in FTD,
but the fnal cortcal area of the ARAS, the frontal cortex, is afected. In the frontal variant, the
frontostriatal circuit is also strongly afected reduced vascularizaton in ACC. Hippocampus shows
reduced metabolism frontohippocampal circuit afected. Dysfuncton of ACC and hippocampus
expresses itself in disinhibited behavior, typical for a patent with frontal variant of FTD. Clinical
manifestaton of strictly prefrontal dysfuncton would result in apathy.
Frontal variant of FTD is also primarily characterized by cognitve, behavioral and personality
disturbances that are related to EF. Impairments of episodic memory do not occur untl later in the
disease progress. Behavioral disturbances characteristc of frontal FTD are: disinhibited behavior,
reduced impulse control, ant-social behavior, stereotypical behavior, compulsiveness, Klüver-Bucy
syndrome and apathy (may be due to impairment in voliton). Their regulatng capacites decline
progressively, making them very dependent on their environment.
Voliton, purposive acton / self-regulaton, and efectve performance (all EF) are impaired in the
frontal variant of FTD. Memory decline does not occur in early stages, making FTD patents easily
distnguishable from AD and amnestc MCI patents. Later; anterograde amnesia, recogniton beter
than actve recall and impairment in remote memory (frontal associaton areas). Intact functons:
visuospatal abilites, naming, word-picture matching, performance of semantc tasks, recent memory
and orientaton.
Temporal variant
Temporal variant occurs more rarely than frontal variant. Atrophy mainly in ventromedial PFC and
hippocampus. Neuronal loss found in anterior and inferior temporal lobes, partcularly in the lef
hemisphere (parahippocampal gyrus and fusiform gyrus). Relaton between ARAS and temporal FTD
not examined. Brain areas that play a role in specifc functonal circuits and that are afected include:
PFC, hippocampus, parahippocampal gyrus. This results mainly in dysfuncton of frontohippocampal
and hippoparietal circuits. Atrophy of hippocampus is not a consistent fnding though.
Difering symptomatology seen in lef and right hemisphere afected. Those with lef hemisphere
afected show decline in semantc knowledge (anomia, word fnding difcultes, and repettve
speech), and tend to be socially pleasant. Those with right hemisphere afected also show aphasia,
but more ofen also behavioral and personality problems in inital stages. Verbal and physical threats
are ofen expressed by these patents. Depression occurs in both groups, but nature of depression
