Studies by Ruth S Ogden, PhD, and Catharine Montgomery, Liverpool John Moores University found that time rarely feels like it is passing at a constant rate; instead, it expands and contracts from one activity to the next. This is especially true when one is under the influence of drugs or alcohol. Drugs such as cocaine, methamphetamine, and alcohol appear to make time speed up, whereas haloperidol and marijuana appear to slow time down. Drugs alter perceived time by affecting the speed of our internal clock and the amount of attention that we pay to time. Whilst such time-altering effects are generally perceived as pleasant and harmless, there is some evidence to suggest that the effects may be long-lasting. A study of the perception of the passage of time during the Covid-19 during lockdown in the United Kingdom, revealed that perception of time passing was unaltered for about 20 percent of those studied. It was distorted for the other 80 percent. About 40 percent thought time went quickly; the other 40 percent felt like time dragged.