Model D

[Petter]

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3032992/

Midbrain dopamine neurons are well known for their strong responses to rewards and their critical role in positive motivation. It has become increasingly clear, however, that dopamine neurons also transmit signals related to salient but non-rewarding experiences such as aversive and alerting events. Here we review recent advances in understanding the reward and non-reward functions of dopamine. Based on this data, we propose that dopamine neurons come in multiple types that are connected with distinct brain networks and have distinct roles in motivational control. Some dopamine neurons encode motivational value, supporting brain networks for seeking, evaluation, and value learning. Others encode motivational salience, supporting brain networks for orienting, cognition, and general motivation. Both types of dopamine neurons are augmented by an alerting signal involved in rapid detection of potentially important sensory cues. We hypothesize that these dopaminergic pathways for value, salience, and alerting cooperate to support adaptive behavior.



https://www.frontiersin.org/articles...019.00334/full

Dopamine and noradrenaline are crucial neuromodulators controlling brain states, vigilance, action, reward, learning, and memory processes. Ventral tegmental area (VTA) and Locus Coeruleus (LC) are canonically described as the main sources of dopamine (DA) and noradrenaline (NA) with dissociate functions. A comparison of diverse studies shows that these neuromodulators largely overlap in multiple domains such as shared biosynthetic pathway and co-release from the LC terminals, convergent innervations, non-specificity of receptors and transporters, and shared intracellular signaling pathways. DA–NA interactions are mainly studied in prefrontal cortex and hippocampus, yet it can be extended to the whole brain given the diversity of catecholamine innervations. LC can simultaneously broadcast both dopamine and noradrenaline across the brain. Here, we briefly review the molecular, cellular, and physiological overlaps between DA and NA systems and point to their functional implications. We suggest that DA and NA may function in parallel to facilitate learning and maintain the states required for normal cognitive processes. Various signaling modules of NA and DA have been targeted for developing of therapeutics. Understanding overlaps of the two systems is crucial for more effective interventions in a range of neuropsychiatric conditions.



https://www.intechopen.com/chapters/55400

The decrease in central serotonergic activity was associated with negative emotional state, poor impulse control, aggressive behavior...



https://www.frontiersin.org/articles...016.00024/full

Since 5-HT release increases in the basolateral amygdala (BLA) during both fear memory acquisition and expression...



https://www.psychologytoday.com/us/b...rest-and-anger

I do not entirely agree with Tomkins on this point. Darwin does use the term attention to refer to what might be considered the affect of interest. When speaking of dogs, he noted: “…if his attention be suddenly aroused, he instantly pricks his ears to listen…” (Darwin, 1872 [Ekman, 1998, p. 283]). Darwin then turned to humans: “When the attention is concentrated for a length of time with fixed earnestness on any object or subject, all the organs of the body are forgotten and neglected… Therefore, many of the muscles tend to become relaxed, and the jaw drops from its own weight… Or again, if an attention continues long and earnestly absorbed, all our muscles become relaxed, and the jaw, which was at first suddenly opened, remains dropped. Thus, several causes concur towards this same movement, whenever surprise, astonishment or amazement is felt” (p. 284).

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He has also linked up attention with surprise, which is consistent with Tomkins’ idea of interest, fear, and surprise all being related: they all depend on the rapidity of stimulus increase. As noted previously, surprise is elicited by the more rapid stimulus increase, fear next, and interest by yet slower incoming stimuli.



https://en.wikipedia.org/wiki/Interest_(emotion)

Facial expression of intense interest (emotion), which includes jaws being dropped, tongue being stuck upward and outward, and pupils being dilated.



https://www.britannica.com/science/norepinephrine

norepinephrine, also called noradrenaline, substance that is released predominantly from the ends of sympathetic nerve fibres and that acts to increase the force of skeletal muscle contraction...



https://www.medicalnewstoday.com/art...0#relationship

Neurotransmitters do not act independently.

They interact with and affect each other to maintain a careful chemical balance within the body. There are strong links between the serotonin and dopamine systems, both structurally and in function.

In some cases, serotonin appears to inhibit dopamine production, which means that low levels of serotonin can lead to an overproduction of dopamine. This may lead to impulsive behavior, due to the role that dopamine plays in reward seeking behavior.

Serotonin inhibits impulsive behavior, while dopamine enhances impulsivity.

Dopamine and serotonin have opposite effects on appetite; whereas serotonin suppresses it, low levels of dopamine can stimulate hunger.



https://www.theatlantic.com/health/a...otions/283560/

This leaves us with four "basic" emotions, according to this study: happy, sad, afraid/surprised, and angry/disgusted. These, the researchers say, are our biologically based facial signals—though distinctions exist between surprise and fear and between anger and disgust, the experiment suggests that these differences developed later, more for social reasons than survival ones.



https://www.tomkins.org/what-tomkins...d-personality/

An intensity of gaze, eyebrows down, “track, look, listen” is the face of interest.

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The smile, lips widened up and out, is the visible evidence of joy. The innate affect is triggered by a decreasing stimulus—perhaps a reduction in hunger or loneliness, or relief of pain.



https://www.jax.org/news-and-insight...ind-depression

People with clinical depression often have increased levels of monoamine oxidase A (MAO-A), an enzyme that breaks down key neurotransmitters, resulting in very low levels of serotonin, dopamine and norepinephrine.



https://www.verywellmind.com/seroton...ome-p2-2584316

While SSRIs are sometimes prescribed to help treat anxiety, some research suggests that high levels of serotonin may be associated with anxiety disorders including social anxiety disorder and panic disorder. Studies suggest that an overactive serotonin system impacts the fear centers in the brain, which may lead to anxiety symptoms.