A study involving young (average age 22) and older adults (average age 77) showed participants pictures of overlapping faces and places (houses and buildings) and asked them to identify the gender of the person. While the young adults showed activity in the brain region for processing faces (fusiform face area) but not in the brain region for processing places (parahippocampal place area), both regions were active in the older adults.
Latest Research News
If our brains are full of clusters of neurons resolutely only responding to specific features (as suggested in my earlier report), how do we bring it all together, and how do we switch from one point of interest to another?
Recent rodent studies add to our understanding of how estrogen affects learning and memory. A study found that adult female rats took significantly longer to learn a new association when they were in periods of their estrus cycle with high levels of estrogen, compared to their ability to learn when their estrogen level was low. The effect was not found among pre-pubertal rats. The study follows on from an earlier study using rats with their ovaries removed, whose learning was similarly affected when given high levels of estradiol.
An experiment with congenitally deaf cats has revealed how deaf or blind people might acquire other enhanced senses. The deaf cats showed only two specific enhanced visual abilities: visual localization in the peripheral field and visual motion detection. This was associated with the parts of the auditory cortex that would normally be used to pick up peripheral and moving sound (posterior auditory cortex for localization; dorsal auditory cortex for motion detection) being switched to processing this information for vision.
The issue of “mommy brain” is a complex one. Inconsistent research results make it clear that there is no simple answer to the question of whether or not pregnancy and infant care change women’s brains. But a new study adds to the picture.
A seven-year study involving 271 Finns aged 65-79 has revealed that increases in the level of homocysteine in the blood were associated with increasing risk of developing Alzheimer’s (each micromolar increase in the concentration of homocysteine increased the risk of Alzheimer's by 16%), while increases in the level of vitamin B12 decreased the risk (each picomolar increase in concentration of B12 reduced risk by 2%). A larger study is needed to confirm this. 17 people (6%) developed Alzheimer’s over the course of the study.
Comparison of the brains of 22 smokers and 21 people who have never smoked in their lives has revealed that the left medial orbitofrontal cortex of the smokers was on average smaller than that of the non-smokers. Moreover, this reduction was greater the more cigarettes were smoked daily, and as a function of how long they had smoked. The region is involved in reward, impulse control, and decision-making, suggesting that fewer neurons there may mean you have to work harder for reward, and that your ability to curb your impulses and make decisions is impaired.
Following on from earlier research suggesting that simply talking helps keep your mind sharp at all ages, a new study involving 192 undergraduates indicates that the type of talking makes a difference. Engaging in brief (10 minute) conversations in which participants were simply instructed to get to know another person resulted in boosts to their executive function (the processes involved in working memory, planning, decision-making, and so on).
We can see shapes and we can feel them, but we can’t hear a shape. However, in a dramatic demonstration of just how flexible our brain is, researchers have devised a way of coding spatial relations in terms of sound properties such as frequency, and trained blindfolded people to recognize shapes by their sounds. They could then match what they heard to shapes they felt. Furthermore, they were able to generalize from their training to novel shapes.
A Chinese study involving 153 older men (55+; average age 72), of whom 47 had mild cognitive impairment, has found that 10 of those in the MCI group developed probable Alzheimer's disease within a year. These men also had low testosterone, high blood pressure, and elevated levels of the ApoE4 protein.
The findings support earlier indications that low testosterone is associated with increased risk of Alzheimer's in men, but it’s interesting to note the combination with high blood pressure and having the ApoE4 gene. I look forward to a larger study.