Chronic stress in early life causes anxiety, aggression in adulthood, neurobiologists find

In recent years, behavioral neuroscientists have debated the meaning and significance of a plethora of independently conducted experiments seeking to establish the impact of chronic, early-life stress upon behavior — both at the time that stress is experienced, and upon the same individuals later in life, during adulthood.These experiments, typically conducted in rodents, have on the one hand clearly indicated a link between certain kinds of early stress and dysfunction in the neuroendocrine system, particularly in the so-called HPA axis (hypothalamic-pituitary-adrenal), which regulates the endocrine glands and stress hormones including corticotropin and glucocorticoid.Yet the evidence is by no means unequivocal. Stress studies in rodents have also clearly identified a native capacity, stronger in some individuals than others, and seemingly weak or absent in still others, to bounce back from chronic early-life stress. Some rodents subjected to early life stress have no apparent behavioral consequences in adulthood — they are disposed neither to anxiety nor depression, the classic pathologies understood to be induced by stress in certain individuals.Today, a research team led by Associate Professor Grigori Enikolopov of Cold Spring Harbor Laboratory (CSHL) reports online in the journal PLoS One the results of experiments designed to assess the impacts of social stress upon adolescent mice, both at the time they are experienced and during adulthood. Involving many different kinds of stress tests and means of measuring their impacts, the research indicates that a “hostile environment in adolescence disturbs psychoemotional state and social behaviors of animals in adult life,” the team says.The tests began with 1-month-old male mice — the equivalent, in human terms of adolescents — each placed for 2 weeks in a cage shared with an aggressive adult male. The animals were separated by a transparent perforated partition, but the young males were exposed daily to short attacks by the adult males. This kind of chronic activity produces what neurobiologists call social-defeat stress in the young mice. These mice were then studied in a range of behavioral tests.”The tests assessed levels of anxiety, depression, and capacity to socialize and communicate with an unfamiliar partner,” explains Enikolopov. These experiments showed that in young mice chronic social defeat induced high levels of anxiety helplessness, diminished social interaction, and diminished ability to communicate with other young animals. Stressed mice also had less new nerve-cell growth (neurogenesis) in a portion of the hippocampus known to be affected in depression: the subgranular zone of the dentate gyrus.Another group of young mice was also exposed to social stress, but was then placed for several weeks in an unstressful environment. Following this “rest” period, these mice, now old enough to be considered adults, were tested in the same manner as the other cohort.In this second, now-adult group, most of the behaviors impacted by social defeat returned to normal, as did neurogenesis, which retuned to a level seen in healthy controls. …

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Spring styles for kids! ($50 Carter’s giveaway)

~This post on spring styles for kids was written in partnership with Carter’s & The Motherhood. Opinions and collages are my own.SERIOUSLY hating this winter. I’m not a cold-weather person anyway, but I haven’t seen the grass (even if it is dead) since… November? And it’s been unbearably cold, too, so it’s not like we get to take the kids out to play in the snow much. Who else is ready for some SUNSHINE?! Some RAIN instead of snow! FLIP FLOPS instead of boots! SUNGLASSES instead of hats & gloves! Me, please!!!Last weekend I pulled out my warm-weather clothes and my sandals. When the warm weather finally hits, I will be ready! So I’ve been shopping for my kids, too. Ya know, it …

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New pathway for fear discovered deep within brain

Fear is primal. In the wild, it serves as a protective mechanism, allowing animals to avoid predators or other perceived threats. For humans, fear is much more complex. A normal amount keeps us safe from danger. But in extreme cases, like post-traumatic stress disorder (PTSD), too much fear can prevent people from living healthy, productive lives. Researchers are actively working to understand how the brain translates fear into action. Today, scientists at Cold Spring Harbor Laboratory (CSHL) announce the discovery of a new neural circuit in the brain that directly links the site of fear memory with an area of the brainstem that controls behavior.How does the brain convert an emotion into a behavioral response? For years, researchers have known that fear memories are learned and stored in a small structure in the brain known as the amygdala. Any disturbing event activates neurons in the lateral and then central portions of the amygdala. The signals are then communicated internally, passing from one group of neurons to the next. …

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Life is good!

Good soaking rain here – fabulous for our garden and all of the plants that are coming up due to our beautiful Spring weather, plus the new plants that I have been busy putting into pots and in the garden. In a month it should look wonderful … then lol our hot dry weather will start once again and we will have to be careful with the tank water and hope we get rain then for the garden and to fill up the tanks … however that is a couple of months away thank goodness.Well today’s visit to day chemotherapy ward at John Fawkner Hospital in Melbourne took an hour by car – good traffic flow and we were there on time for our appointment at 11am. Picc actually had …

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