Psychologists have been assessing reaction times since long before the field of psychology came into being, and they remain a fundamental part of cognitive psychology experiments today. Generally, psychologists investigate variations in the time required for participants to react to stimuli under different conditions, utilizing these variations as evidence of how cognitive processing differs across those conditions.
Francis Galton, a well-known eugenicist and statistician, amassed a substantial dataset (n=3410) of what are termed ‘simple reaction times’ during the late 19th century. Galton’s approach veered from that of many contemporary psychologists; he explored reaction times as an indicator of individual differences. His hypothesis proposed that differences in processing speed could explain variations in intelligence, and perhaps these variations could be effectively evaluated through recordings of reaction times.
Galton’s data raises an intriguing question—are individuals today quicker or slower than Galton’s subjects, over a century later? According to Galton’s hypothesis, this answer wouldn’t merely indicate if someone could outdraw a Victorian-era gunslinger in a quick-draw competition, but could also provide insights into generational shifts in cognitive abilities at large.
Reaction time (RT) data presents an interesting counterargument to the widely recognized historical rise in IQ scores over generations, referred to as the Flynn Effect. The Flynn Effect astonishes those who believe “kids today” are less polite, intelligent, and disciplined than those of prior generations—a sentiment echoed throughout history, even in Ancient Greece—and those theorists who conjecture that intelligence should decline over time, as more intelligent individuals tend to have fewer offspring.
While the Flynn Effect contradicts the notion of diminishing intelligence, there appears to be promise within the reaction time data. It is possible that Victorian participants genuinely exhibited faster reaction times. Numerous research studies have endeavored to compare Galton’s findings with more contemporary research, with some utilizing identical apparatus and measurement techniques. Silverman (2010) analyzed RTs recorded by young adults across 14 studies starting from 1941, juxtaposing them with Galton’s late 1800s study. With one exception, modern studies revealed longer RTs than those observed by Galton. Although the potential for these discrepancies stemming from inaccurate timing devices was contemplated, it was considered unlikely.
Woodley et al (2015) presented a useful graph illustrating this trend (with Galton’s results positioned at the bottom left). Although the disparity measures only around ~20 milliseconds (or one-fiftieth of a second) across 100 years, in terms of reaction times, it represents a significant difference, suggesting that contemporary participants are roughly 10% slower.
What conclusions can be drawn from this? Generally, a single study, even one encompassing 3000 participants, would not carry significant weight, and alternatives are restricted as there are no young adults from the 19th century available to confirm whether the results could be replicated. It’s lamentable that there are not more intervening studies to examine the plausible hypothesis that 1930s participants might fall between Victorian and modern participants.
Even if this data point is acknowledged, its interpretation is contentious. Does it signify a true decline in cognitive capability? Increased cognitive burdens on other tasks? Variations in motivation? Modifications in experimental design or participant behavior? The conclusions remain open, but naysayers regarding such reactions may cling to hope for the younger generation.
References:
– Irwin, W. S. (2010). Simple reaction time: it is not what it used to be. American Journal of Psychology, 123(1), 39-50.
– Woodley, M. A., Te Nijenhuis, J., & Murphy, R. (2013). Were the Victorians cleverer than us? The decline in general intelligence estimated from a meta-analysis of the slowing of simple reaction time. Intelligence, 41(6), 843-850.
– Woodley, M. A, te Nijenhuis, J., & Murphy, R. (2015). The Victorians were still faster than us. Commentary: Factors influencing the latency of simple reaction time. Frontiers in human neuroscience, 9, 452.