Hippocampal mechanisms involved in the enhancement of fear extinction caused by exposure to novelty

This 2014 Brazilian rodent study provided more information on the workings of the hippocampus. The researchers measured the effects of re-experiencing a fear within a specific context: “Within a restricted time window, a brief exposure to a novel environment enhances the extinction of contextual fear. The enhancement of extinction by the exposure to novelty depends … Continue reading Hippocampal mechanisms involved in the enhancement of fear extinction caused by exposure to novelty

Emotional responses and BDNF methylation

This 2019 German human study found: “A critical role of BDNF [brain-derived neurotrophic factor] methylation in human amygdala response to negative emotional stimuli, whereby: High BDNF methylation rates were for the first time shown to be associated with a high reactivity in the amygdala; and High BDNF methylation and high amygdala reactivity were associated with … Continue reading Emotional responses and BDNF methylation

Reductionism vs. reductionism

This 2004 essay by an evolutionary biologist reviewed his field’s direction in the current century: “Science is impelled by two main factors, technological advance and a guiding vision (overview). A properly balanced relationship between the two is key to the successful development of a science. Without the proper technological advances the road ahead is blocked. … Continue reading Reductionism vs. reductionism

Epigenetic effects of THC differ between female adolescents and adults

This 2017 Italian rodent study found: “THC [delta9-tetrahydrocannabinol, the psychoactive compound of cannabis] exposure affects histone modifications in the brain of female rats in a region- and age-specific manner. Specifically, THC acts on different targets depending on the considered brain area and, remarkably, the adolescent brain is generally more sensitive to THC than the adult … Continue reading Epigenetic effects of THC differ between female adolescents and adults

Use it or lose it: the interplay of new brain cells, age, and activity

This 2015 German review was of aging and activity in the context of adult neurogenesis: “Adult neurogenesis might be of profound functional significance because it occurs at a strategic bottleneck location in the hippocampus. Age-dependent changes essentially reflect a unidirectional development in that everything builds on what has occurred before. In this sense, aging can … Continue reading Use it or lose it: the interplay of new brain cells, age, and activity

The cerebellum’s role in human behavior and emotions

This 2016 Italian human review considered the lower brain’s contributions to an individual’s behavior and temperament: “In evidencing associations between personality factors and neurobiological measures, it seems evident that the cerebellum has not been up to now thought as having a key role in personality. Cerebellar volumes correlate positively with novelty seeking scores and negatively … Continue reading The cerebellum’s role in human behavior and emotions

Fear extinction is the learned inhibition of retrieval of previously acquired responses

This 2014 rodent study showed that fear extinction doesn’t depend on memory retrieval: “These results show that extinction and retrieval are separate processes and strongly suggest that extinction is triggered or gated by the conditioned stimulus even in the absence of retrieval.” The key to my understanding this finding came from a definition in another … Continue reading Fear extinction is the learned inhibition of retrieval of previously acquired responses