Stable and state-dependent impulsivity in Bipolar disorder

Maja Milavec, psychologist, Ph. D. student

Lilijana Šprah, Assistant Professor and Research Fellow

Sociomedical Institute at SRC SASA, Ljubljana, Slovenia

Bipolar disorder

Any of several mood disorders, usually

characterised by alternating episodes of

depression and mania or by episodes of

depression alternating with mild,

non-psychotic excitement.

Impulsivity

is a predisposition toward

rapid, unplanned reactions to

internal or external stimuli

without regard to the negative

consequences of these reactions to the

impulsive individual or to others.

(Moeller, Barratt, Dougherty, Schmitz and Swann, 2001)

- A prominent aspect of Bipolar disorder;

- manic episode;

- can be present during depression;

- complications: suicide, substance abuse, complications

of manic episodes;

- stable or state-dependent;

- emotional modulation of cognitive control (attentional

bias to positive and negative information).

Impulsivity

Aims

1.) Whether emotional valence of stimulus influences

cognitive control in bipolar patients compared to

healthy individuals.

2.) Whether there is an interaction between stable and

state-dependent aspect of impulsivity in bipolar

disorder.

Method

Participants

- 39 bipolar outpatients

- 38 healthy individuals

(matched for age, gender and years of education)

Instruments

Barratt Impulsiveness Scale 11 (BIS-11)

- Questionnaire designed to measure impulsiveness (stable aspect).

- Three subscales: - attention (intention and cognitive instability), - motor (motor impulsiveness and lack of perseverance),- non-planning (lack of self-control and intolerance of

cognitive complexity).

(Patton, Standford and Barratt, 1995)

Affective Go/No-Go Task

- Computer administered;- pictures of negative, positive and neutral

emotional valence taken from International Affective Picture System (IAPS);

- 6 blocks with all combinations (negative/positive etc.).

Go Go No-Go No-Go Go

800 1000 800 1000 800 1000 800 1000 800

Time (ms)

Example:

“If the picture in front of you is PLEASANT, press the RED BUTTON on the keyboard AS FAST AS YOU CAN, other way don’t press

anything.”

Inst

ruct

ions

Reaction times

Bipolar outpatients had longer reaction times to emotional stimuli than healthy individuals.

0

100

200

300

400

500

600

700

800

900

Negative** Neutral* Positive*

emotional valence of targets (Go)

aver

age

reac

tio

n t

imes

BD

controls

* p<0,05; ** p<0,01

Global score

N M SD t p df

BD 39 136,59 12,79-2,280 0,026 73

controls 36 143,17 12,14

Bipolar outpatiens had less correct answers than healthy individuals.

N M SD t df

BIS-11 Attention BD 39 17,64 4,43

2,847** 75controls 38 15,05 3,48

BIS-11 Motor BD 39 21,49 4,94

1,832** 75controls 38 19,63 3,87

BIS-11 Non-planning

BD 39 24,87 5,66

2,839** 75

controls 38 20,76 6,99

BIS-11 Global score

BD 39 64,00 12,83

2,990** 75

controls 38 55,45 12,25

** p<0,01

Bipolar outpatiens had higher levels of trait impulsivity

than healthy individuals.

Bipolar patients with heightened levels of trait impulsivity

underestimated

- target stimuli with positive valence (r = -0,425; p < 0,01),

- distractors with negative (r = -0,331; p < 0,05) and

- distractors with neutral (r = -0,417; p< 0,01) emotional

valence.

Conclusions

- Poorer control of cognitive inhibition

- increased levels of impulsivity and other associated cognitive

impairments;

- emotional valence of stimulus influences cognitive

control in bipolar patients compared to healthy subjects;

- interaction between stable and state-dependent aspect

of impulsivity in bipolar disorder.

Contact

maja.milavec@gmail.com