Addiction, current research

Methamphetamine in Pregnancy Delays Infant Brain Development (Source: Medscape, 09.11.2016)

Infants exposed in utero to methamphetamine or whose mother smoked tobacco while pregnant display delays in motor development and white matter maturation.

Sex Differences

The researchers assessed, over a period of 4 months following birth, white matter microstructure and neurologic development of infants exposed to methamphetamine and/or tobacco prenatally and those of healthy control infants who were not exposed to those substances.

Assessments included quantitative neurologic examination and diffusion tensor imaging, which were performed up to three times through age 4 months, and diffusivities and fractional anisotropy (FA), assessed in seven white matter tracts and four subcortical brain regions.

Methamphetamine and tobacco-exposed infants showed delayed trajectories on active muscle tone. Male infants who were exposed to both stimulants also had significantly delayed trajectories in superior and posterior corona radiata that normalized by age 3 to 4 months. Female infants exposed to both stimulants had persistently lower FA in anterior corona radiata.

Tobacco-exposed infants also showed persistently lower axial diffusion in the thalamus and posterior limb internal capsule. These brain abnormalities were likely due to prenatal stimulant exposure, possibly via epigenetic effects, genetic predisposition, or other prenatal factors not evaluated.

The fact that the neonates exposed to methamphetamine and tobacco already showed the abnormal baseline brain microstructures and active muscle tone, although some but not all of these abnormalities may normalize over the first 4 to 5 months of life.

The findings imply that the effects that we observed are likely due to the effects of prenatal drug (meth+tobacco) exposure on brain development, and not due to other environmental influences during early infancy.

Alarming Increase

The use of stimulants such as methamphetamine by pregnant women has increased “alarmingly” during the past decade, with reports suggesting that up to 92% of women of low socioeconomic status use methamphetamine, two researchers from South Africa note in a linked editorial.

These women also often use tobacco, drink alcohol, or use other illicit substances.

“There seems to be overlap in how these substances affect the developing brain,” write Annerine Roos, PhD, of Stellenbosch University, and Kirsten Ann Donald, MD, PhD, of the University of Cape Town.

“The field of brain imaging for infants is evolving fast,” they add, and this new study “confirms that prenatal exposure to methamphetamine and/or tobacco alters white matter developmental trajectories, and the effects are partly dependent on sex.

In particular, because the rate of white matter maturation and development is particularly pronounced through the first year of life, follow-up at 1 and 2 years of age, when much of the process has stabilized, will be important, Dr Roos and Dr Donald write.

….

Internet Addiction Shows Up In the Brain

(Source: The Little Black Book of Billionaire Secrets  17.01.2012, by Alice G. Walton),

Digital thrills

There’s been a lot of controversy over the concept of Internet Addiction Disorder (IAD), especially as the new DSM-V prepares to launch. Some feel that there’s little evidence to warrant IAD as being recognized as an actual disorder. Others disagree. Earlier research has found some changes in the brain of people who are hooked on the Web, and a new study shows reductions in volume of certain areas of the brain and in its the white matter – the highways of connection between brain cells – of young people who are addicted to the Internet. What’s interesting is that these brain changes mirror the ones in people who are addicted to other kinds of things, like heroin, for example.

Researchers quizzed 35 people between the ages of 14 and 21 about their Internet use and feelings about how it affected their lives. Among the eight questions were some like:

“Do you feel nervous, temperamental, depressed, or sensitive when trying to reduce or quit Internet use?” “Have you taken the risk of losing a significant relationship, job, educational or career opportunity because of the Internet?”  “Have you lied to your family members, therapist, or others to hide the truth of your involvement with the Internet?” “Do you use the Internet as a way of escaping from problems or of relieving an anxious mood (e.g., feelings of helplessness, guilty, anxiety, or depression)?”

If respondents answered “yes” to at least five of the questions, as half of them did, they were tagged as having IAD. To confirm the youngsters’ habits, the researchers asked their family and friends about how much their habits were “disrupting others’ lives despite the consequences.”

Then the participants underwent brain scans to look at any differences that might exist in the brains of the IAD sufferers and in controls. They found several areas of decreased volume in IAD participants, and for some of these areas, there was a negative relationship between volume and the length of time the participants had been addicted to the Internet.  In other words, the longer they were addicted, the less volume they had in certain regions.

There were also altered connections in the white matter tracts between brain cells, which suggests disruptions in how the neurons “talk” to one another.

The areas that were affected in the people who were diagnosed with IAD are thought to govern emotional processing, executive thinking skills and attention, and cognitive control. What’s more, the brain changes found in this study are thought to be similar to those involved in other kinds of addiction, like alcohol and drugs. Earlier research had suggested similar links, but this study seems to add to the growing body of evidence that Internet addiction may actually exist.

People who suffer from IAD don’t just spend a lot of time on the computer, but the authors say they also have significant problems in life, like “impaired individual psychological well-being, academic failure and reduced work performance.”

As always, there’s the lingering question of which came first, the chicken or the egg. In this case, it’s not clear whether people became addicted to the Internet first and brain changes then followed, or whether the brain was already wired differently, predisposing the young brains to addiction.

It will probably take a while to figure out this ever-present question that plagues science. Rather than being a straight either/or situation, it could be more of a back-and-forth: brains could be predisposed (genetically and physiologically) to addiction, then addiction develops, then brain changes exaggerate – and so on and so forth.

It will be interesting to see how the study will affect the debate. Since it seems like we can become addicted to just about anything – substances and behaviors alike – it may not be surprising that Internet addiction is a real thing. More work will be needed to understand the phenomenon more fully, but in the meantime, it can’t hurt to turn off the computer and give your brain a little rest.