Behavior resembling human ADHD seen in dogs
University of Helsinki
"Dogs
share many similarities with humans, including physiological traits and the
same environment. In addition, ADHD-like behaviour naturally occurs in dogs.
This makes dogs an interesting model for investigating ADHD in humans,"
says doctoral researcher Sini Sulkama.
Professor Lohi's research group collected data on more than 11,000 dogs by conducting an extensive behavioural survey.
Hyperactivity, impulsivity and inattention were
examined using questions based on a survey utilised in human ADHD research. The
goal of the study was to identify environmental factors underlying canine
ADHD-like behaviour and potential links to other behavioural traits.
The dog's age and gender as well as the owner's experience of dogs make a difference
"We
found that hyperactivity, impulsivity and inattention were more common in young
dogs and male dogs. Corresponding observations relating to age and gender in
connection with ADHD have been made in humans too," says Jenni
Puurunen, PhD.
Dogs
who spent more time alone at home daily were more hyperactive, impulsive and
inattentive than dogs who spent less time on their own.
"As
social animals, dogs can get frustrated and stressed when they are alone, which
can be released as hyperactivity, impulsivity and inattention. It may be that
dogs who spend longer periods in solitude also get less exercise and attention
from their owners," Sulkama muses.
The
researchers discovered a new link between hyperactivity and impulsivity, and
the owner's experience with dogs, as the two traits were more common in dogs
who were not their owners' first dogs. The causality of this phenomenon remains
unclear.
"People
may pick as their first dog a less active individual that better matches the
idea of a pet dog, whereas more active and challenging dogs can be chosen after
gaining more experience with dogs," explains Sulkama.
Significant
differences between breeds
Breeding
has had a significant effect on the breed-specific behaviour of different dog
breeds. Differences between breeds can also indicate genes underlying the
relevant traits.
"Hyperactivity
and impulsivity on the one hand, and good concentration on the other, are
common in breeds bred for work, such as the German Shepherd and Border Collie.
In contrast, a more calm disposition is considered a benefit in breeds that are
popular as pets or show dogs, such as the Chihuahua, Long-Haired Collie and
Poodle, making them easier companions in everyday life. Then again, the ability
to concentrate has not been considered as important a trait in these breeds as
in working breeds, which is why inattention can be more common among pet
dogs," Professor Lohi says.
Link
to other behavioural problems
The
study confirmed previously observed interesting links between hyperactivity,
impulsivity and inattention, and obsessive-compulsive behaviour, aggressiveness
and fearfulness. ADHD is also often associated with other mental disorders and
illnesses. For example, obsessive-compulsive disorder (OCD) often occurs in
conjunction with ADHD. In dogs, OCD-like obsessive-compulsive behaviour can
appear as, among other things, tail chasing, continuous licking of surfaces or
themselves, or staring at 'nothing'.
"The
findings suggest that the same brain regions and neurobiological pathways
regulate activity, impulsivity and concentration in both humans and dogs. This
strengthens the promise that dogs show as a model species in the study of ADHD.
In other words, the results can both make it easier to identify and treat
canine impulsivity and inattention as well as promote ADHD research," Sulkama
sums up.