Brain Changes in Response to Experience

“Rats kept in a lively environment for 30 days show distinct changes in brain anatomy and chemistry compared with animals kept in a dull environment.” Ref “Before 1960, the brain was considered by scientists to be immutable, subject only to genetic control. In the early sixties, however, investigators were seriously speculating that environmental influences might be capable of altering brain structure. By 1964, two research laboratories proved that the morphology and chemistry of the brain could be experientially altered. Since then, the capacity of the brain to respond to environmental input, specifically “enrichment,” has become an accepted fact among neuroscientists, educators and others. In fact, the demonstration that environmental enrichment can modify structural components of the rat brain at any age altered prevailing presumptions about the brain’s plasticity. The cerebral cortex, the area associated with higher cognitive processing, is more receptive than other parts of the brain to environmental enrichment. The message is clear: Although the brain possesses a relatively constant macrostructural organization, the ever-changing cerebral cortex, with its complex microarchitecture of unknown potential, is powerfully shaped by experiences before birth, during youth and, in fact, throughout life. It is essential to note that enrichment effects on the brain have consequences on behavior. Parents, educators, policy makers, and individuals can all benefit from such knowledge.”...

Response of the Brain to Enrichment

Response of the Brain to Enrichment Enrichment: Neural grafting to experimental neocortical infarcts improves behavioral outcome and reduces thalamic atrophy in rats housed in enriched but not standard environments. THE EFFECTS OF ENRICHMENT ON THE CEREBRAL CORTEX “What do we mean by “enrichment” for the rats who have served as the animal of choice for most of these studies? Thirty six Long-Evans rats were sorted into three experimental conditions using 12 animals in each group: 1) enriched 2) standard or 3) impoverished environments. All animals had free access to food and water and similar lighting conditions. Eventually, it was determined that animals maintained in their respective environments from the age of 30 days to 60 days developed the most extensive cerebral cortical changes. For the enriched environment, the 12 animals lived together in a large cage ( 70 x 70 x 46 cm) and were provided 5-6 objects to explore and climb upon (e.g., wheels, ladders, small mazes). The objects were changed two to three times a week to provide newness and challenge; the frequent replacement of objects is an essential component of the enriched condition. The combination of “friends” and “toys” was established early on by Krech as vital to qualify the experiential environment as “enriched.” For the standard environment, the animals were housed 3 to a small cage ( 20 x 20 x 32 cm) with no exploratory objects. For the impoverished environment, one animal remained alone in a small cage with no exploratory objects. The numbers of animals placed in these separate conditions were based on the manner in which the routine housing was established in...

Traumatic stress: effects on the brain

“Brain areas implicated in the stress response include the amygdala, hippocampus, and prefrontal cortex. Traumatic stress can be associated with lasting changes in these brain areas. Traumatic stress is associated with increased cortisol and norepinephrine responses to subsequent stressors. Antidepressants have effects on the hippocampus that counteract the effects of stress. Findings from animal studies have been extended to patients with post-traumatic stress disorder (PTSD) showing smaller hippocampal and anterior cingulate volumes, increased amygdala function, and decreased medial prefrontal/anterior cingulate function. In addition, patients with PTSD show increased cortisol and norepinephrine responses to stress. Treatments that are efficacious for PTSD show a promotion of neurogenesis in animal studies, as well as promotion of memory and increased hippocampal volume in PTSD.”...

Pregnancy Changes the Brain in Ways That May Help Mothering

Pregnancy Changes the Brain in Ways That May Help Mothering “Pregnancy changes a woman’s brain, altering the size and structure of areas involved in perceiving the feelings and perspectives of others, according to a first-of-its-kind study. Most of these changes remained two years after giving birth, at least into the babies’ toddler years. And the more pronounced the brain changes, the higher mothers scored on a measure of emotional attachment to their babies. In the study, researchers scanned the brains of women who had never conceived before, and again after they gave birth for the first time. The results were remarkable: loss of gray matter in several brain areas involved in a process called social cognition or “theory of mind,” the ability to register and consider how other people perceive things.”...

Response to Fear & Anxiety causes Physical and Mental health Changes

Response to Fear & Anxiety causes Physical and Mental health Changes “Impact of Fear and Anxiety” *Facing Fear & Anxiety Home *Impact of fear and anxiety *Work with threats *Manage chronic fear *More resources “Fear is a human emotion that is triggered by a perceived threat. It is a basic survival mechanism that signals our bodies to respond to danger with a fight or flight response. As such, it is an essential part of keeping us safe. However, when people live in constant fear, whether from physical dangers in their environment or threats they perceive, they can become incapacitated. How fear works: Fear prepares us to react to danger. Once we sense a potential danger, our body releases hormones that: Slow or shut down functions not needed for survival (such as our digestive system). Sharpen functions that might help us survive (such as eyesight). Our heart rate increases, and blood flows to muscles so we can run faster. Our body also increases the flow of hormones to an area of the brain known as the amygdala to help us focus on the presenting danger and store it in our memory. Living under constant threat has serious health consequences. Physical health. Fear weakens our immune system and can cause cardiovascular damage, gastrointestinal problems such as ulcers and irritable bowel syndrome, and decreased fertility. It can lead to accelerated ageing and even premature death. Memory. Fear can impair formation of long-term memories and cause damage to certain parts of the brain, such as the hippocampus. This can make it even more difficult to regulate fear and can leave a person anxious most of the time. To someone in chronic fear,...