Chapter 8

Question 1

Name the three different subtypes of frontotemporal dementia.

Answer 1

(1) Frontal variant, (2) Temporal variant and (3) progressive non-fluent aphasia.

Question 2

To which chromosome is FTD related?

Answer 2

Chromosome 17

Question 3

For the frontal variant, where is the main neuropathology found? Which pathways / neurotransmitter systems are mostly affected?

Answer 3

Most severe atrophy in frontal, lateral anterior temporal and parietal cortex, as well as in the hippocampus.

Deficits are seen in the serotonergic system, leading to impaired glucose metabolism in the frontal lobe. Moreover, there is impairment seen in the nigrostriatal dopaminergic system.

The frontostriatal circuit is strongly affected, as well as the frontohippocampal circuit (due to reduced metabolism in the hippocampus). Reduced vascularization in the anterior cingulate cortex also influences the nigrostriatal circuit.

Question 4

For the frontal variant, what are typical symptoms? Which cognitive functions remain intact?

Answer 4

Cognitive, behavioural and personality disturbances (related to executive functions): disinhibited behaviour, reduced impulse control, anti-social behaviour, stereotypical behaviour, compulsiveness, apathy, Klüver-Bucy snydrome (hyper-orality, hyper-sexuality).

Later stage: episodic memory impairments (recognition better than active retrieval; remote memory).

Remain intact: orientation, recent memory, visuospatial abilities, naming, word-picture matching, semantic tasks.

Question 5

For the temporal variant, where is the main neuropathology found? Which pathways / neurotransmitter systems are mostly affected?

Answer 5

Atrophy of the ventromedial PFC, the hippocampus and the anterior and inferior temporal lobes (particularly left hemisphere).
Dysfunction in the frontohippocampal and hippoparietal circuits.

Question 6

For the temporal variant, what are typical symptoms?

Answer 6

Executive functions are relatively preserved. Patients function well in daily life.

Semantic dementia: decrease in category fluency, decrease in understanding infrequent words, decline in remote memory.

Depending on the side of the affected hemisphere:

(1) Left: primarily semantic memory loss (anomia), word finding difficulties and repetitive speech. Are socially pleasant and show normal social behaviour. Depression (anhedonia, feelings of worthlessness, crying).
(2) Right: more behavioural, personality and psychiatric disturbances. Behaviour is socially clumsy, agitated and irritated. Verbal and physical threats occur frequently. Depression (lack of insight, denial of disease, eccentric behaviour, bad hygiene).

Later stages: prosopagnosia.