Brain Activation during Memory Encoding in Type 2 Diabetes Mellitus: A Discordant Twin Pair Study
Table 2
Cognitive scores and brain volumes stratified by zygosity.
Cognitive score
Monozygotic (8 pairs)
Dizygotic (14 pairs)
Type 2 diabetes Mean (SD)
No diabetes Mean (SD)
Type 2 diabetes Mean (SD)
No diabetes Mean (SD)
NART-R FSIQ
108.9 (8.7)
107.6 (9.9)
107.4 (9.3)
107.9 (7.9)
HVLT delayed recall
9.4 (2.1)
9.6 (1.7)
8.9 (2.7)
9.9 (2.0)
HVLT recognition
11.9 (0.4)
11.4 (1.1)
11.3 (0.8)
11.1 (1.1)
Rey complex figure copy
34.2 (2.4)
35.6 (0.7)
35.0 (1.4)
34.1 (2.7)
Rey complex figure delayed recall
19.3 (5.7)
18.5 (7.0)
19.5 (6.6)
20.1 (6.4)
WMS3 mental control
27.3 (7.2)
26.2 (5.8)
24.4 (5.4)
24.7 (4.1)
WMS3 digits total
19.6 (5.3)
19.1 (4.5)
17.8 (3.4)
18.4 (3.3)
SRT correct latency (mean)
260.9 (56.9)
273.9 (56.3)
283.1 (65.9)
249.2 (33.4)
PAL total errors (raw)
27.6 (25.2)
34.4 (41.5)
28.0 (33.6)
24.7 (25.3)
fMRI task, word errors
29.5 (16.4)
28.8 (19.8)
22.6 (15.7)
21.4 (12.2)
fMRI task, drawing errors
18.5 (14.5)
14.7 (10.9)
21.6 (14.4)
22.0 (13.7)
Total hippocampal volume (mL)
4.8 (0.4)
4.7 (0.6)
4.3 (0.5)
4.4 (0.6)
Gray matter volume (mL)
633.7 (53)
664.6 (78)
641.9 (70)
631.0 (49)
White matter volume (mL)
470.2 (48)
494.4 (56)
463.6 (63)
461.8 (45)
White matter lesion volume (mL)
5.2 (2.9)
6.2 (4.8)
4.3 (1.5)
4.5 (2.2)
NART-R: national adult reading test-revised; HVLT: Hopkins verbal learning test; WMS3: Wechsler memory scale version 3; FSIQ: full scaled intelligence quotient; SRT: simple reaction time from the CANTAB; PAL: paired associates learning test from the CANTAB; SD: standard deviation; fMRI: functional magnetic resonance imaging. None of the comparisons above reached statistical significance of .
