BDNF, relative preference, and reward circuitry responses to emotional communication

Abstract

Brain derived neurotrophic factor (BDNF) regulates neural development and synaptic transmission. We have tested the hypothesis that functional variation in the BDNF gene (Val66Met polymorphism, rs6265) affects brain reward circuitry encoding human judgment and decision-making regarding relative preference. We quantified relative preference among faces with emotional expressions (angry, fearful, sad, neutral, and happy) by a keypress procedure performed offline to measure effort traded for viewing time. Keypress-based relative preferences across the ensemble of faces were mirrored significantly by fMRI signal in the orbitofrontal cortex, amygdala, and hippocampus when passively viewing these faces. For these three brain regions, there was also a statistically significant group difference by BDNF genotype in the fMRI responses to the emotional expressions. In comparison with Val/Met heterozygotes, Val/Val individuals preferentially sought exposure to positive emotions (e.g., happy faces) and had stronger regional fMRI activation to aversive stimuli (e.g., angry, fearful, and sad faces). BDNF genotype accounted for approximately 30% of the variance in fMRI signal that mirrors keypress responses to these stimuli. This study demonstrates that functional allelic variation in BDNF modulates human brain circuits processing reward/aversion information and relative preference transactions.

Neurobiology of Value Integration: When Value Impacts Valuation

“…This is in line with evidence suggesting that the ventral part of the medial PFC and OFC encodes the reward value of choice options Daw et al, 2006;Kim et al, 2006;Plassmann et al, 2008;Gasic et al, 2009;Hare et al, 2009;Kahnt et al, 2010Kahnt et al, , 2011Philiastides et al, 2010;Smith et al, 2010). Talmi and colleagues (2009) have demonstrated that activity in this region increases with rewards and is attenuated by the prospect of pain.…”

“…The subgenual anterior cingulate cortex (sgACC) has been shown to encode both positive and negative values (Blood et al, 1999;Plassmann et al, 2010). Also, the amygdala represents values independent of valence (Breiter et al, 1996Becerra et al, 2001;Gasic et al, 2009). Furthermore, these structures play a key role in both affect (Phelps et al, 2004) and pain regulation (Bingel et al, 2006;Wiech et al, 2008).…”

The Role of BDNF-TrkB Signaling in the Pathogenesis of PTSD

“…Indeed, both BDNF and TrkB expression are vital for reward responsiveness in BDNF knockout and replacement models in mice [91,92]. In humans, there is some evidence that the BDNF met allele diminishes reward seeking and aversive stimuli avoidance behavior [7]. In conclusion, diminished BDNF signaling in the NAcc may contribute to decreased reward responsiveness, leading to the restricted range of affect, or emotional numbing, commonly seen in individuals with PTSD.…”

“…This signaling pathway has been implicated in a wide variety of psychiatric diseases, with significant changes in levels of BDNF and TrkB mRNA and protein levels in the hippocampal and pre-frontal cortical regions in the post-mortem brains of individuals with various psychiatric diseases [1–4]. More specific to PTSD, changes in this pathway have been shown to affect contextual fear learning, extinction, and expression and reward responsiveness [5–7]. These alterations may be partially responsible for the development of clinical hallmarks of PTSD such as intrusive memories, hyperarousal, fear, and restricted range of affect (Figure 1).…”

The association of brain derived neurotrophic factor gene variants with behaviour traits in sika deer (<i>Cervus nippon</i>)

“…It is abundantly expressed in the mammalian hippocampus and involved in a crucial role in various higher cognitive processes, including decision making, learning, and memory performance induced by environmental conditions (Gasic et al, 2009;Kang et al, 2010). Environmental factors such as physical exercise, dietary restriction, and housing conditions affect BDNF levels (Adlard et al, 2004).…”