Healthy
Conditions
Keywords
Eye-tracking, Losartan, looming fear
Brief summary
The main aim of the present study is to investigate the effects of orally administered losartan on the perception of time-to-collision of threatening and non-threatening stimuli by combining a validated looming fear eye-tracking paradigm with a randomized between-subject placebo-controlled pharmacological trial design.
Detailed description
Animal models and initial findings in humans suggest a role of the angiotensin II antagonist losartan in socio- emotional processes. At the same time, the visual system's remarkable ability to perceive and interpret impending threats, notably through the looming phenomenon- a distinct pattern of optical expansion on the retina as objects approach, theoretically allows for precise estimation of the time-to-collision (TTC). It was demonstrated that the affective content of looming stimuli influences perceived TTC, with threatening objects judged as approaching sooner than non-threatening objects, hinting at a nuanced interaction between emotional valence and temporal perception. Within this context the present study aims to examine whether angiotensin II blockade via Losartan modulates the perception of time-to-collision towards threatening and non-threatening stimuli. To this end, healthy individuals will undergo a double-blind, between-subjects, placebo-controlled pharmaco-eye-tracking experiment and receive a single oral dose of losartan (50 mg) or placebo before performing a looming fear task 90 minutes after administration. The task paradigm will encompass threatening (butterfly, rabbit) and non-social (spider, snake) stimuli to examine the emotion-specific effects of losartan.
Interventions
DRUGLosartan
Administration of losartan tablets (50 mg)
DRUGPlacebo
Administration of placebo tablets
Sponsors
University of Electronic Science and Technology of China
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
BASIC_SCIENCE
Masking
DOUBLE (Subject, Investigator)
Masking description
Randomized placebo-controlled double-blind between-subject design
Eligibility
Sex/Gender
ALL
Age
18 Years to 40 Years
Healthy volunteers
Yes
Inclusion criteria
* Healthy subjects who volunteer to participate and are able to fully understand and agree with this study by written informed consent. * Normal or corrected-normal version
Exclusion criteria
* History of neuropsychiatric diseases. * History of cardiac disease, including arrhythmias, aortic stenosis, or congestive heart failure; history of syncope or unexplained loss of consciousness. * History of hepatic diseases, including cholestasis, biliary obstructive disease, or severe liver dysfunction. * History of renal diseases, including renal stones or renal failure. * History of hyponatremia(Serum sodium \<135mmol/L) or hyperkalemia (Serum potassium\>5.5mmol/L); history of diabetes mellitus or diabetes insipidus * Known hypersensitivity or allergic reaction to any medication or hormone; strong allergic reaction to food. * Infections such as COVID-19 or influenza, or unexplained fever. * Subjects with hypertension (BP ≥130/80mmHg) or hypotension (BP ≤ 90/60mmHg). * History of alcohol or drug abuse; smoker (≥ 10 cigarettes or ≥ 3 cigars or ≥ 3 pipes/day); smoker using e-cigarettes. * Blood donation (≤ 1 month prior to administration). * Take oral contraceptives or receive hormonal medications in the three months prior to the experiment.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Ratio of judged-time-to-collision to actual-time-to-collision for threatening versus non-threatening stimuli after losartan administration | 120 minutes - 150 minutes after treatment | Comparison of the ratio between the judged time to collision and the actual time to collision between the treatment groups for threatening (spider, snake) and non-threatening (rabbit, butterfly) stimuli. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| First saccade latency(ms) for threatening versus non-threatening stimuli after losartan administration | 120 minutes - 150 minutes after treatment | Comparison of first saccade latencies between treatment groups for threatening (spider, snake) and non-threatening (rabbit, butterfly) stimuli. |
| Fixation duration(ms) for threatening versus non-threatening stimuli after losartan administration | 120 minutes - 150 minutes after treatment | Comparison of mean fixation durations between treatment groups for threatening (spider, snake) and non-threatening (rabbit, butterfly) stimuli. |
Countries
China
Contacts
Primary ContactWeihua Zhao, Dr
Outcome results
None listed