Meditation and brain physiology: any togetherness?

Mindfulness is typically defined as nonjudgmental attention to experiences in the present moment suggest a two-component model of mindfulness, where the first component is the regulation of attention in order to maintain it on the immediate experience, and the second component involves approaching one’s experiences with an orientation of curiosity, openness, and acceptance, regardless of their valence and desirability. Mindfulness is typically cultivated in formal meditation practices, such as sitting meditation, walking meditation, or mindful movements.

Behavioral findings affirm that it has been proved from various approaches that mindfulness training program did show reduction in emotional interference compared to a relaxation meditation. Physiological studies also support the proposition that meditation training leads to decreased emotional reactivity and facilitates a return to emotional baseline after reactivity.

Neural mechanisms:

During emotion regulation, prefrontal control systems modulate emotion generative systems, such as the amygdala, which is responsible for the detection of affectively arousing stimuli (Ochsner & Gross, 2005). More specifically, these prefrontal structures include dorsal regions of the lateral prefrontal cortex (PFC) that have been implicated in selective attention and working

memory; ventral parts of the PFC implicated in response inhibition; the ACC, which is involved in monitoring control processes; and the dorso-medial PFC implicated in monitoring one’s affective state (Modinos, Ormel, & Aleman, 2010; Ochsner & Gross, 2008). A typical pattern detected when individuals deliberately regulate affective responses is increased activation within the PFC and decreased activation in the amygdala (Beauregard, Levesque, & Bourgouin, 2001; Harenski & Hamann, 2006; Schaefer et al., 2002), suggesting that PFC projections to the amygdala exert an inhibitory top-down influence (Banks, Eddy, Angstadt, Nathan, & Phan, 2007).

Evidence:

Perspectives on Psychological Science 6(6) 537– 559

Prolactin endorses liver regeneration

The hormone prolactin is probably best known for its role in stimulating milk production in mothers after giving birth. But apart from the lacto-production, prolactin also has an important function in the liver. This organ has the highest number of prolactin receptors in the body, ports that allow this hormone to enter liver cells. There, prolactin signals these cells to multiply and new blood vessels to grow to fuelthis organ's expansion.

Wondering if these properties might be useful to encourage the liver to regrow after surgery to remove part of it-sometimes necessary to treat cancer or other liver diseases, or to donate liver tissue for transplants-Carmen Clapp of the Universidad Nacional Automoma de Mexico and her colleagues worked with animal models on both ends of a prolactin spectrum: rats that overproduced the hormone, and mice specially bred to have no prolactin receptors, the equivalent of a dearth of the hormone since prolactin can't enter these animals' cells.

The researchers found that the animals with extra prolactin had larger livers, regenerated their livers faster after partial removal, and were significantly more likely to survive that liver surgery compared to the animals that couldn't process prolactin. Researchers may also come out with direct correlation of molecular pathways and affirm a solution.