The research is among the projects being worked on by the new University of Otago academic neurosurgery research unit, which is the first of its kind in the country.
Belgian neurosurgeon Prof Dirk De Ridder, who leads the unit and is head of neurosurgery at Dunedin Hospital, said the unit, along with Associate Prof Patrick Manning, would be looking at how some obese people's brains functioned differently than those of people in a healthy weight range.
''When you eat, you eat because the brain tells you that you need more energy. Now, normally when you have got enough energy stored, then your brain says `it's enough' and the way it does this is by creating satiety.''
However, some obese people did not have properly functioning dopamine receptors, which meant they had to eat more food before their brains told them they were full.
By gaining an understanding of this difference the researchers could help discover new weight-loss treatments for obese people.
These treatments could take advantage of neuromodulation, which involves using electrical or magnetic stimulus to change brain activity, to replicate healthy brain activity so obese people feel full quicker.
In the ''far future'' this could involve having a brain implant to modulate activity, but it could also involve using medication.
The research could have implications for other disorders which involve ''dysfunctional reward systems'', including alcoholism and obsessive-compulsive disorder.
''We know that people with alcohol addiction also have problems with these dopamine receptors,'' he said.
Another project the unit was working on, along with the anatomy and physiology departments, was researching ways of ''talking to the brain in a language it understands''.
This meant being able to use techniques such as neuromodulation to replicate the signals sent in healthy brains in the brains of people with certain disorders.
''We want to mimic nature, we want to mimic how the brain conveys the message of `this is important or this is not important'.''
Prof De Ridder, who has a 50/50 split between research and being a clinician, said he was enjoying working in Dunedin after taking up the position in February.
He was grateful for the continued fundraising effort to endow the Chair in Neurosurgery, which allowed the unit to carry out interesting research. Recent donations included $27,000 from the Manchester Unity Lodge and $20,000 from the Clinton Lions.
New Zealand has been named as one of the fattest countries in the world.
A report by the United Nations Food and Agricultural Organisation ranked New Zealand as having the 12th-highest number of overweight and obese people.
The United States, which previously had the worst record, was overtaken by neighbouring Mexico, where 70% of adults are overweight and a third obese.
The study found 27% of New Zealanders were obese, just behind Lebanon and alongside Slovenia.
Australia was the 17th-fattest nation and Britain 19th.
A survey earlier this year listed New Zealand adults as being on average the second-heaviest among 50 countries, which prompted warnings of a looming medical crisis.
The average New Zealander was estimated to weigh 81.3kg last year, lighter only than the average American, who weighed 82.7kg, according to figures compiled by the Bloomberg news service, using data from the World Health Organisation, the OECD and a survey funded by the US Agency for International Development.
However, adults in American Samoa are still officially the fattest in the world.
Additional reporting APNZ
