The human body does not have time sensing receptors; thus, there is no association between time and sensory-specific systems 1 . We have receptors under the skin for sensing touch, temperature, pain, pressure, and vibration. In addition, we have proprioceptors in muscles and tendons, which continuously generate action potentials to the central nervous system with information about the length and tension of muscles; this signaling allows us to make accurate movements. We also have highly specialized sensory systems, such as vision, hearing, olfaction, and gustation, which provide us with environmental information. Although we are not endowed with time receptors 2,3 , our brains have an inherent ability to process time through the functions of neuronal mechanisms and neurotransmitters.We carry watches to know the hour precisely, but we do not need similar devices to determine whether it is cold or whether a sound is loud or soft. Similarly, our perception of time refers to subjective experience and depends on an internal clock. The subjective duration of events may be based on brain units that accumulate over time 4,5,6,7 . It is commonly said that "time passes faster" in older people 8 , which may be due to central dopamine-related mechanisms and memory 9,10 . This study aimed to estimate the passage of time in different age groups, to test the truth of this saying. METHODThis study included 233 healthy subjects, including 129 women. Three groups were formed according to age: Group 1 comprised 86 subjects, aged 15-29 years; the mean age was 22.4 years. Group 2 comprised 76 subjects, aged 30-49 years; the mean age was 38.9 years. Group 3 comprised 71 subjects, aged 50-89 years; the mean age was 59.7 years. Each of the participants was asked to count mentally with eyes closed the passage of 120 s (2 min). When the participant ABSTRACTOur internal clock system is predominantly dopaminergic, but memory is predominantly cholinergic. Here, we examined the common sensibility encapsulated in the statement: "time goes faster as we get older". Objective: To measure a 2 min time interval, counted mentally in subjects of different age groups. Method: 233 healthy subjects (129 women) were divided into three age groups: G1, 15-29 years; G2, 30-49 years; and G3, 50-89 years. Subjects were asked to close their eyes and mentally count the passing of 120 s. Results: The elapsed times were: G1, mean = 114.9 ± 35 s; G2, mean = 96.0 ± 34.3 s; G3, mean = 86.6 ± 34.9 s. The ANOVA-Bonferroni multiple comparison test showed that G3 and G1 results were significantly different (P < 0.001). Conclusion: Mental calculations of 120 s were shortened by an average of 24.6% (28.3 s) in individuals over age 50 years compared to individuals under age 30 years.Keywords: time perception; age; timing; aging. RESUMONosso sistema de relógio interno é predominantemente dopaminérgico, mas a memória é predominantemente colinérgica. Neste estudo, examinamos a assertiva comum que "o tempo passa mais rápido para pessoas mais velhas". Objetivo: Medir o int...