July 25, 2019
The tendency to procrastinate may have a genetic basis, at least in women, early research suggests.
Investigators found women who tend to put off tasks have a genetic predisposition towards higher dopamine levels in the brain that may contribute to the behavioral trait.
"Dopamine is an important neurotransmitter that has been related to cognitive flexibility. Though this is not entirely bad, it comes at the cost of distraction," Caroline Schluter, doctoral candidate, Department of Psychology, Ruhr University Bochum, Germany, told Medscape Medical News.
While higher dopamine levels may improve cognitive flexibility, it may also promote distraction by "fostering the cognitive processing of disturbing influences. This, again, could turn us away from our actual goal leading to procrastination," said Schluter.
The study was published online July 3 in the journal Social Cognitive and Affective Neuroscience.
Many people are prone to procrastinate, but the genetic underpinnings of this trait are largely unknown, the investigators note.
A key factor that influences a person's ability to tackle specific tasks directly instead of putting them off is the ability to initiate cognitive, motivational, and emotional control mechanisms. These "metacontrol" mechanisms are related to dopaminergic signaling.
This prompted researchers to zero in on the tyrosine hydroxylase (TH) gene. Depending on the expression of the gene, individuals' brains have differing amounts of neurotransmitters from the catecholamine family, to which the neurotransmitter dopamine belongs.
The 278 healthy adults showed a sex-dependent effect of TH genotype on decision-related action control. In women, homozygous carriers of the C-allele had higher decision-related action scores and were less apt to procrastinate than carriers of at least one T-allele.
In contrast, T-allele carriers showed lower decision-related action control, and were therefore more likely to procrastinate.
"Since T-allele carriers are considered to have higher TH activities and increased levels of dopamine, our study suggests that in women higher dopamine base levels are likely to increase the propensity to procrastinate," the researchers write.
No Clinical Implications ... Yet
The researchers note it is conceivable that the elevated dopamine level observed in T-allele carriers increases the amount of context information processed in the working memory and this, in turn, might make it easier for an individual to become distracted and unable to focus.
There was no significant effect of TH genotype on action control in men.
Estrogen may be behind the gender differences as it indirectly influences dopamine production in the brain, and this may be one reason women appear to be more susceptible to genetic differences in dopamine levels, the researchers note.
"It is quite hard to speculate about the clinical implications of our findings since we exclusively worked with participants who were mentally and neurologically healthy," said Schluter.
"However, it would certainly be interesting to investigate the relationship between genes and tendency to procrastinate in clinical samples as well. Here, patients with a chronic dopamine deficiency, as seen in Parkinson's disease or patients with impulse control disorder, might be of interest," she said.
Bernhard Hommel, PhD, Leiden University Institute for Brain and Cognition, the Netherlands, who reviewed the study for Medscape Medical News, said its "logic and rationale make sense." However, he added, "one needs to consider that the sample size is pretty small for genetic analyses."
The study was supported by the DFG (Deutsche Forschungsgemeinschaft) and Mercur Foundation. Schlüter and Hommel have reported no relevant financial relationships.