The brains of pregnant women appear to shrink during late pregnancy, according to research which offers an explanation for cognitive problems some women complain of before and after giving birth. The doctors at the Royal Postgraduate Medical School in London found that it can take up to six months for the women’s brains to regain their full size.
Anita Holdcroft, the anaesthetist in charge of the study, said poor concentration, lack of co-ordination, and memory problems in late pregnancy may be linked to the changes in brain size she and her colleagues observed.
A set of three-dimensional images of the brains of 10 healthy women were taken, using magnetic resonance imaging (MRI) in late pregnancy, six to eight weeks after delivery, and then up to six months later.
According to a report in New Scientist magazine, Dr Holdcroft and colleagues found that as the woman’s body and physiology returned to the non-pregnant state, their brains increased in size. It is possible that their brains were swelling from a normal state but this is unlikely, Dr Holdcroft told a meeting of the Physiological Society in Sheffield earlier this month.
The findings follow a study of women who suffer very high-blood pressure – pre-eclampsia – in which a build-up of fluid causes swelling; potentially fatal seizures can follow. “We assumed that their brains would also swell but last year we found that they shrink,” Dr Holdcroft said. When the study was extended to healthy women, it was found that brain shrinkage appeared to be a normal feature of pregnancy.
The investigators believe that the brain changes are more likely to be the result of changes in the volume of individual cells rather than in the quantity of brain cells, Dr Holdcroft told the magazine. In addition, the team found that the pituitary gland, which lies at the base of the brain, showed the opposite effect – increasing in size during pregnancy, when it is responsible for producing reproductive hormones – and then diminishing in size in the months after pregnancy.
By Liz Hunt Health Editor from independent UK
Intimate couples developed a memory system where they rely on each other on remembering things.
New research from Macquarie University in Australia reveals that intimate couples become part of an interpersonal cognitive system where each is dependent on the other to fill in certain memory gaps.
On the face of it, it seems obvious that we should work with other people when trying to recall shared information. But research shows this isn’t always the case; individual recall tends to be more efficient compared to social remembering. But as an updated study by Celia Harris and her colleagues shows, there are some cases when “shared remembering” can be effective.
For their study, the researchers looked at the various ways intimate couples collaborated on simple memory tasks, as well as their conversations about shared past experiences. They also asked them about their everyday memory compensation strategies to learn about the complex ways they coordinate their material and interpersonal resources.
The British Psychological Society explains more
[In a previous study], the researchers noticed that although couples did more poorly at listing their shared holidays when recalling together, these social sessions were filled with anecdotes and tangents that weren’t generated in the solo sessions. This inspired them to depart from testing memory for lists of words and events, and to explore the amount of rich, in-depth information remembered by couples about experienced events. They found these social exchanges led to clear collaborative memory benefits, which could take three forms:
1. “New information” such as finally snatching an elusive name of a musical thanks to a chain of prompts between the two parties.
2. Richer, more vivid descriptions of events including sensory information.
3. Information from one partner painting things in a new light for the other.
Differences between the couples were crucial. Those who structured their approach together and were more prepared to riff off the other’s contributions did better than those who were more passive or critical. Richer events were also better remembered by partners who rated their intimacy as higher.
Interestingly, older adults experienced the greatest memory difficulties with first-hand autobiographical information — and this is exactly where long-term couples gained the biggest benefit from remembering together. So, as we grow older, we offset our unreliable episodic systems by drawing on the support offered by a partner — a shared resource.
By George Dvorsky, PSYCHOLOGY