The role of dopamine in bias and disengagement, two mechanisms implicated in visuospatial attention.

The role of dopamine in bias and disengagement, two mechanisms implicated in visuospatial attention. - The role of dopamine in visuospatial attention

Status

Active, not recruiting

Phases

Unknown

Study type

Interventional

Source

NL-OMON

Registry ID

NL-OMON36039

Enrollment

Registered

2012-01-24

Start date

2012-04-05

Completion date

Unknown

Last updated

2024-05-06

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Geen aandoening, haloperidol wordt toegediend om de neurobiologie van aandacht te onderzoeken The neurobiology of visuospatial attention.

Interventions

Haloperidol

Eligibility

Age

18 Years to 99 Years

Inclusion criteria

Inclusion criteria: - Age 18 - 45 yrs.

Exclusion criteria

Exclusion criteria: Any of the following (assessed by interview): 1. History of cardiovascular problems 2. Liver disease 3. Current use of any medication 4. History of cocaine use. 5. Diagnosed psychopathology 6. Hypersensitivity to haloperidol 7. Hyperthyroidism 8. History of epilepsy

Design outcomes

Primary

Measure	Time frame
Behavioural measures: In the VSC (Visual Spatial Cueing) paradigm: the validity effect in ms (RT valid cued target - RT invalid cued target). A larger validity effect reflects either more bias, or less disengagement. In the stop task paradigm, the time needed (in milliseconds) to abort a prepotent response: the Stop Signal Reaction Time (SSRT); SSRT reflects inhibition and related disengagement but is also dependent on bias. Neurophysiological (Event Related Potentials, task related brain activity) endparameters in the VSC: 1) Parietal cue Event Related Potential (ERP) components. These are the Anterior Directing Attention Negativity (ADAN) and the Late Directing Attention Positivity (LDAP). Both are related to bias. 2) P1 ERP (following a validly cued target); associated with bias. 3) Late Positive Deflection (LPD) ERP (following an invalidly cued target); associated with disengagement. Neurophysiological (ERP) endparameters in the stop task: 1) N2 ERP (following the onset of a stopsignal), associated with disengagement. 2) LPD ERP (following the onset of a stopsignal), associated with disengagement.	—

Measure

Time frame

Behavioural measures: In the VSC (Visual Spatial Cueing) paradigm: the validity effect in ms (RT valid cued target - RT invalid cued target). A larger validity effect reflects either more bias, or less disengagement. In the stop task paradigm, the time needed (in milliseconds) to abort a prepotent response: the Stop Signal Reaction Time (SSRT); SSRT reflects inhibition and related disengagement but is also dependent on bias. Neurophysiological (Event Related Potentials, task related brain activity) endparameters in the VSC: 1) Parietal cue Event Related Potential (ERP) components. These are the Anterior Directing Attention Negativity (ADAN) and the Late Directing Attention Positivity (LDAP). Both are related to bias. 2) P1 ERP (following a validly cued target); associated with bias. 3) Late Positive Deflection (LPD) ERP (following an invalidly cued target); associated with disengagement. Neurophysiological (ERP) endparameters in the stop task: 1) N2 ERP (following the onset of a stopsignal), associated with disengagement. 2) LPD ERP (following the onset of a stopsignal), associated with disengagement.

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Secondary

Measure	Time frame
Spontaneous motor activity (measured by an actigraph) Dyskinesia (measured by Velocity Scaling)	—

Countries

Netherlands

Outcome results

None listed

Source: NL-OMON (via WHO ICTRP)