A randomized, cross-over, dose-response trial of tyrosine and its effect on working memory in healthy elderly and young people

Completed

• Conditions: cognitive performance; mental health; 10013511

• Registration Number: NL-OMON41127
• Lead Sponsor: Wageningen Universiteit

Brief Summary

Not available

Detailed Description

Not available

Study Timeline

• Last Update Posted: 11 June 2024

Recruitment & Eligibility

• Status: Completed
• Sex: Not specified
• Target Recruitment: 34

Inclusion Criteria

• Aged 18-35 years or aged 60-75 years
• Normal and stable weight (BMI 18.5-25 kg/m2 and weight 50-95 kg)
• Willing to abstain from blood donation during the study
• Dutch-speaking
• Non-smoking
• Normal or corrected-to-normal vision

Exclusion Criteria

• Thyroid problems, such as hyperthyroidism, hypothyroidism, thyroid cancer
• Using medication that can interfere with tyrosine*s action; monoamine oxidase inhibitors and other antidepressants, sympathomimetic amines, and opioids
• Following a low-protein diet as prescribed by a dietician or physician
• Parkinson*s Disease
• Depression
• Use of tyrosine supplements
• Being allergic or having a dislike to the product carrier (banana-flavored yoghurt)
• Bad venous access, as judged by the research nurse
• Mini Mental State Examination (MMSE) score < 24 (to exclude cognitive impaired participants, only for elderly participants)
• Estimated IQ < 85 (based on Nederlandse Leestest voor Volwassenen (NLV) -score)
• (History of) clinically significant psychiatric disorder
• (History of) clinically significant neurological disorder, such as brain infarct, chronic migraine, major depression
• Under treatment for cardiac or vascular diseases and use of medication for these conditions
• General medical conditions, such as repetitive strain injury (RSI) or sensori-motor handicaps, as judged by the investigator
• Alcohol consumption of more than 14 (women) or 21 (men) units per week

Study & Design

• Study Type: Interventional
• Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
<p>The primary study parameter is tyrosine plasma concentration at T0, T90, T120,<br /><br>T150, T180, T210 and T240. </p><br>

Secondary Outcome Measures

Name	Time	Method
<p>The secondary study parameter is performance on the n-back working memory task<br /><br>measured by accuracy (total number of hits) and reaction time (ms).</p><br>