Investigating the Effect of Caffeine Consumption on Speech Understanding in Noise in Young Adults

Caffeine is a widely consumed substance worldwide and is often used to increase alertness and improve cognitive functions. Caffeine stimulates brain activity by binding to adenosine receptors, which increases alertness instead of sleepiness. Studies on the effects of caffeine on cognitive functions have shown that it improves basic cognitive functions such as attention, reaction time, and alertness, while a less pronounced effect is seen on sensory functions such as vision and hearing. However, no study has been found investigating the effect of caffeine consumption on understanding speech in noise. Understanding speech in noise is a skill that includes not only auditory functions but also cognitive functions. This skill is affected by cognitive elements such as selective attention and executive functions. In this context, it is thought that this study, which aims to examine the relationship between caffeine and understanding speech in noise, will contribute to the literature. 60 participants between the ages of 18-30 will be included in this study. Participants will consist of individuals without hearing loss (SSO<25 dB nHL), no history of neurological or psychological disorders, non-smokers, and those who do not use ototoxic drugs. Participants will be randomly divided into a placebo group that consumes decaffeinated coffee and a study group that consumes coffee containing 300 mg caffeine. The Turkish Matrix Test will be administered 30 minutes after coffee consumption. In addition, participants will be asked to keep a caffeine diary for one week to determine their daily caffeine consumption and will be asked to fill out the Caffeine Use Disorder Scale. Thus, they will be divided into low and high caffeine consumption groups and their speech understanding skills in noise will be compared.

Study Overview

• Status: Recruiting
• Conditions: Hearing
• Intervention / Treatment: Other: Experimental; Other: Placebo

• Study Type: Interventional
• Enrollment (Estimated): 60
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Merve MERAL ÇETİNKAYA; Phone Number: +905382835187; Email: mervemeral1@aydin.edu.tr

Study Locations

• Turkey
  • Istanbul, Turkey
    • Recruiting
    • Istanbul Aydin University
    • Contact: Merve MERAL ÇETİNKAYA; Phone Number: +905382835187; Email: mervemeral1@aydin.edu.tr

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• For both groups, it was planned to include individuals who had no hearing loss (SSO<25 dB nHL), no history of neurological or psychological disorders, were non-smokers, and did not use ototoxic drugs.

Exclusion Criteria:

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Other
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Experimental; Approximately 280 grams of caffeine containing coffee is given.	Other: Experimental; Approximately 280 grams of caffeine containing coffee will be given
Placebo Comparator: Placebo; Decaffeinated coffee will be provided.	Other: Placebo; Decaffeinated coffee will be given.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Turkish Matrix Test	The test will be administered using the Oldenburg Measurement Application (OMA) software. Using the adaptive procedure, the signal-to-noise ratio (SNR-50) at which the individual repeats the words correctly at 50% will be found. Accordingly, the noise will be given continuously, kept constant at 65 dB SPL throughout the test. The test will start at 0 dB signal-to-noise ratio (SNR). There are sentences consisting of 5 words in the test. If the participant repeats at least three of the five words presented to him/her correctly, the SNR will decrease and if he/she does not repeat at least three words correctly, the SNR will increase. A total of 20 sentences will be presented to the participants.	Before and 30 minutes after drinking coffee

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Caffeine Use Disorder Scale	This scale, developed by Ágoston et al. (2018), consists of 10 items based on the nine criteria recommended for caffeine use disorder specified in the Diagnostic and Statistical Manual of Mental Disorders (DSM-5). The scale measures the severity of caffeine use symptoms in the last twelve months. As the scale score increases, caffeine use disorder symptoms also increase. Kaya et al. (2021) conducted the Turkish validity and reliability study of the scale. The total score that can be obtained from this scale varies between 10 and 40 and there is no reverse item. The questions are graded as "1=never, 2=sometimes, 3=often, 4=very often" and are interpreted as caffeine use disorder increases as the scale score increases. In the reliability analysis, Cronbach alpha internal consistency coefficient was found to be 0.86, and the intraclass correlation coefficient was found to be 0.83.	Before consuming caffeine.

Collaborators and Investigators

• Sponsor: Istanbul Aydın University

Study record dates

Study Major Dates

• Study Start (Actual): April 12, 2025
• Primary Completion (Estimated): September 13, 2025
• Study Completion (Estimated): April 13, 2026

Study Registration Dates

• First Submitted: April 14, 2025
• First Submitted That Met QC Criteria: April 21, 2025
• First Posted (Actual): April 24, 2025

Study Record Updates

• Last Update Posted (Actual): April 24, 2025
• Last Update Submitted That Met QC Criteria: April 21, 2025
• Last Verified: April 1, 2025

More Information

Terms related to this study

• Other Study ID Numbers: 41/2025; 1919B012442147 (Other Grant/Funding Number: The Scientific and Technological Research Council of Türkiye (TÜBİTAK))

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No