Table 2

Neuropsychological performance of patients and control subjects

OW patients

NW patients

OW controls

NW controls

DM*

OW*

Interaction*

<Go/NoGo task>

Discriminability (d')

2.66 ± 0.48

2.39 ± 1.0

3.14 ± 0.59

3.28 ± 0.46

0.001^‡

0.648

0.215

Commission errors

9.8 ± 3.8

10.1 ± 3.8

6.6 ± 4.2

5.5 ± 2.9

0.002^‡

0.74

0.463

Omission errors

0.4 ± 0.9

3.8 ± 8.0

0.2 ± 0.4

0.1 ± 0.3

0.049^†

0.081

0.072

RT (ms)

356 ± 28

330 ± 59

339 ± 37

363 ± 35

0.104

0.629

0.009^†

Post-error slowing (ms)

379 ± 66

322 ± 68

348 ± 57

343 ± 40

0.525

0.035^†

0.054

<Reversal and extinction tasks>

Errors after reversal

1.7 ± 3.0

1.2 ± 0.4

1.1 ± 0.3

1.0 ± 0.4

0.977

0.358

0.448

Errors after extinction

7.6 ± 3.7

6.4 ± 4.0

8.7 ± 5.2

5.1 ± 3.0

0.894

0.029^†

0.340

<WCST>

Achievement scores

5.4 ± 1.0

4.6 ± 1.3

5.9 ± 0.6

5.6 ± 0.5

0.218

0.117

0.773

% perseverative errors

2.7 ± 6.4

8.2 ± 10.1

4.2 ± 9.0

3.2 ± 5.3

0.458

0.296

0.147

Neuropsychological data are given as means ± SD. *Data were analysed by covariate analysis of variance (ANCOVA) with age as a covariate, and the main effects and interaction of type 2 diabetes and being overweight are shown as P values. ^†P<0.05, ^‡P < 0.007 with ANCOVA. OW, overweight; NW, normal weight; DM, type 2 diabetes mellitus; RT, reaction time in unplanned responses to the Go stimuli.

Ishizawa et al. BioPsychoSocial Medicine 2010 4:1   doi:10.1186/1751-0759-4-1