WELL CONNECTED Neurons (green) in the lateral hypothalamus connect with those in the ventral tegmental area of mice’s brains to contribute to compulsive sugar consumption. ~~ Courtesy of Edward Nieh/MIT
Dopaminergic neurons and their projections. Axons of dopaminergic neurons located in the substantia nigra pars compacta ascend rostrally as the nigrostriatal pathway and provide dopaminergic innervation to neurons located in the caudate nucleus and putamen (striatum). Axons of another group of dopaminergic neurons that are located in the ventral tegmental area ascend in the median forebrain bundle to provide dopaminergic innervation to the frontal and cingulate cortices.
Ketamine blocks glutamate NMDA receptors in the brain. Increases brain-derived neurotrophic factor (BDNF, important for long-term memory and the creation of new synapses) and restores healthy mushroom-shaped spines on the dendrites of neurons in the prefrontal cortex. It may also affect the monoamines norepinephrine (NE) and dopamine. In rats, increased the firing rate of NE neurons in the locus coeruleus and also increased spontaneous firing dopamine cells in the ventral tegmental area.
The ventral tegmental area (VTA), a group of neurons at the very centre of the brain, plays an especially important role in this circuit. The VTA receives information from several other regions that tell it how well various fundamental needs, and more specifically human needs, are being satisfied.
Ventral Tegmental Area (VTA) is the area that synthesizes dopamine, which then sends to nucleus accumbens. Nucelus accumbens is the pleasure center, and it is stimulated by the neurotransmitter dopamine from VTA. VTA also sends dopamine to prefrontal cortex which regulates and controls these impulses. The locus coeruleus is the area packed with norepinephrine; and when stimulated by a lack of the addictive substance, will drives the person to do anything necessary to obtain a fix.
The pain network consists of the dorsal anterior cingulate cortex (dACC), insula (Ins), somatosensory cortex (SSC), thalamus (Thal), and periaqueductal gray (PAG). This network is implicated in physical and social pain processes. The reward or pleasure network consists of the ventral tegmental area (VTA), ventral striatum (VS), ventromedial prefrontal cortex (VMPFC), and the amygdala (Amyg). This network is implicated in physical and social rewards.
Activity in the Ventral Tegmental Area (VTA) due to satisfaction from LOVE