Table 1 Earlier reports of cognitive function in SCA14

Klebe et al. [17]

1 tested - normal global IQ

15

Patient 1: deficits in abstract thinking and shifting, verbal fluency and inhibitory control, subcortical dementia.

2 patients extensively tested

Patient 2: memory deficit and impaired executive functions, impaired working memory, increased sensibility to proactive interference in memory, tendency to perseverate. 2 out of 15 characterized as demented on clinical impression only

Stevanin et al. [27]

4 out of 7 indications of low IQ and difficulty with abstract thinking*

18

Patient 1: executive function deficit, difficulties with memory encoding and retrieval, attention deficit, cognitive slowing, impaired working memory, concept shifting, abstract thinking, resistance to interference and inhibitory control

2 patients extensively tested

Patient 2: impaired executive functions, tendency to perseverate, attention deficit, lack of inhibitory control

Hiramoto et al. [25]

n.a.

5

1 patient described with mental retardation, 4 patients described with no intellectual disturbance

Miura et al. [26]

Total IQ (66,73,93), verbal IQ (79,77,90), performance IQ (58,74,99)

3

Visual memory deficit in 1