Shorter Winter Days Triggers Agression Hormones Differently in Male and Female Hamsters

 

A recent study at Indiana University shows a hormonal mechanism in hamsters that connects short winter days with agression in females, and differs from the mechanism that controls this in males.

 

A quote from a psychologist who was part of the research states "The results show for the first time that melatonin acts directly on the adrenal glands in females to trigger a 'seasonal aggression switch' from hormones in the gonads to hormones in the adrenal glands -- a major contrast to how this mechanism works in males."

 

It was originally thought that the aggression came from sex hormones in the gonads.

 

Melatonin is a hormone that rises in the body during darkness and lowers during daylight. The hormone from the adrenal gland is dehydroepiandrosterone, or DHEA, a sex steroid shown to affect aggression levels in mammals and birds, and possibly humans. In another previous study, Demas' lab found that melatonin, in concert with a hormone secreted by the brain's pituitary gland called adrenocorticotropic increases the output and enhances the effects of DHEA from adrenal glands in males.

 

In contrast, Rendon and colleagues' new study reveals that melatonin acts directly on the adrenal glands in females to trigger the release of DHEA, without the need for the pituitary hormone.

 

DHEA can be converted into estrogen or androgens, which affects aggression. In female hamsters it compensates for low amounts of estradiol that occurs in the winter.

The research was conducted in Siberian hamsters, or Phodopus sungorus, a species with a similar adrenal system to humans. About 130 hamsters were exposed to long days for a week, after which 45 were exposed to shorter days for 10 weeks.

Strength of brain connectivity varies with fitness level in older adults

A new study led by Michelle Voss shows that there is a relationship between fitness levels of adults and strength of connections between different parts of the brain. The findings suggest that adults with a greater cardiovascular fitness level have stronger brain connections, and this is suggested to improve long term memory. 

Using functional magnetic resonance imaging, Voss and colleagues measured the strength of these connections throughout the brain in younger and older adults at rest. As expected, the team confirmed that most connections were weaker for older adults when compared with younger adults.They decided to build on these findings and test the role that cardiovascular fitness has on resting brain connectivity. 

A quote from Voss states "An encouraging pattern in the data from our study and others is that the benefits of fitness seem to occur within the low-to-moderate range of endurance, suggesting that the benefits of fitness for the brain may not depend on being extremely fit."

This study suggests that there is a positive relationship between fitness and brain connectivity as people age. This study can be extremely beneficial as it may be able to prevent/reduce the amount of people who suffer from brain problems related to forgetting by regularly exercising, such as dementia. 

The Anxiety and Depression study (Kinderman et Al)

Kinderman et Al performed a huge study in the UK with over 32,000 adults. The study was about depression anxiety and the causes behind it.

In this study they found that the most common cause for anxiety or depression was traumatic life events, such as the death of a family member/ loved one. However, to the researchers surprise they also found that the way in which the individuals coped/dealt with their anxiety and depression contributed towards it almost as much as the traumatic event itself. 

They identified 3 major contributors, they were:

• rumination - This means excessive fixation on negative thoughts, feelings and beliefs.
• Self-blame - This is when the individual turns the blame onto them-self.
• Lack of Adaptive coping - This is when the individual is unable to help them-self by asking for help/advice from friends or family members, or eating properly and exercising.

(Self-blame is most common among people who grew up with emotional neglect)

My Opinion - 

This study is very interesting as it shows the importance of how we deal with anxiety and depression as it has been suggested to be just as influential as the event itself. This shows that coping techniques are a huge factor in dealing with depression, and the correct coping technique would be to seek advice from others, not to dwell on negative thoughts, eat well and exercise and stop blaming yourself. 

The Persuasion Technique

The technique is called the 'But You Are Free' technique. This is when you ask somebody to do something and add on to the end of the question the fact that they are free to chose. 

A recent review of the 42 psychology studies carried out on this technique has shown that it is surprisingly effective given how simple it is (Carpenter, 2013). All in all, over 22,000 people have been tested by researchers. Across all the studies it was found to double the chances that someone would say ‘yes’ to the request.People have been shown to donate more to good causes, agree more readily to a survey and give more to someone asking for a bus fare home.

There have been further studies where the type of words have been changed from 'but you are free to chose' to 'but don't feel obliged'. These studies have found that the actual wording is not important, but what is important is that it still implies that the person is able to make their choice. 

It also underlines the fact that people hate to be hemmed in or have their choices reduced. We seem to react against this attempt to limit us by becoming more closed-minded

My opinion

I find this piece of research particularly because myself, and many others, have probably succumb to this persuasion technique without even realising it, and have probably used it on other people without even knowing. I am interested in the fact that the simple suggesting that you have the right to make a choice makes people more willing to say yes. Knowing that you are free to make up your own mind and are not being forced into something makes you more willing to do it. 

Can cocoa extract really prevent Altzheimers disease?

New reseatch claims that cocoa extract may help prevent age-related cognitive disorders like Alzheimer's disease. 

The micronutrients found in chocolate – known as polyphenols – were studied by Dr. Giulio Maria Pasinetti and colleagues. Their data suggests there's evidence to support the development of a cocoa extract as a natural remedy to maintain and promote brain health, especially age-related neurodegenerative disorders like Alzheimer's disease. The cocoa polyphenols are believed to reduce the production and build-up of beta-amyloid and tau proteins that have been linked to Alzheimer's disease.

The health benefits of chocolate have also been explored in previous studies, highlighting its protective power against heart disease, gas and bloating ​and a means of replenishing oxidative stress related to muscle fatigue.

I think that this piece of research is extremely interesting as I am very interested in diseases/disorders of the brain. I find brain cognition to be a fascinating subject and looking into all the connections and different functions of the brain.

The Bystander Effect

The bystander effect is the belief that the more people to witness a scene, such as a murder or crash, the less likely any one individual is to do anything about it. 

In 1964 a woman called Kitty Genovese was murdered in New York in front of numerous amounts of people, of which only one of the bystanders shouted to the murderer "leave her alone". 

Psychologists decided to test this theory. The psychologists were John Darley and Bibb Latane. 

They used an actor to pretend that they were having a life-threatening seizure, of which the participants could not see but could hear them, like Milgram's obedience study. They found that the results were very similar to the Kitty Genovese case. The more people aware that the person is in need of help,  the less likely they are to do anything about it. 

My Opinion

I believe this to be very true. When there is a big group of people, you naturally assume that out of all the people around you, somebody else would have done/ being doing something to help the person in need. However, if this is what everybody thinks then eventually nobody will help the person, which could result in severe consequences like the Kitty Genovese case. 

Elderly related words provoke slow walk

An experiment in 1996 by John Bargh et Al investigated whether exposing people to words portrayed as being old would effect the participants behaviour - walking. They found that because the participants were exposed to these elderly words, they subsequently walked away from the laboratory more slowly and elderly-like. This experiment is related to 'social priming' which means we are much more susceptible to influence than we realise. The study has been attempted again on different occasions and some have been unsuccessful in finding any results similar to the original, where as others have been successful in finding similar results. This has caused much debate and disagreement over whether the results found in John Bargh et Al's research has any significance or validity at all.