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38 EDUCATIONAL AWEMainta Dialuna, 2 October 2023
Dopamine’s Multifaceted Role:
Unveiling New Dimensions
in Neurotransmission
DOPAMINE, the renowned
neurotransmitter synonymous with
mood and pleasure, is experiencing
heightened attention. Recent discus-
sions encompass “dopamine hacking,”
viral social media content, and
podcasts that delve into optimizing the
effects of this molecule on mood and
productivity. However, cutting-edge
neuroscience research now challenges
the prevailing limited understanding of
dopamine’s functionality.
A delightful meal generates positive In a groundbreaking August 2023
Dopamine is among the brain’s reward prediction errors, likely leading study, researchers at Northwestern
neurotransmitters, small messengers to return visits. Conversely, a disap- University’s Dombeck Lab explored
facilitating communication between pointing meal yields negative reward dopamine function according to
neurons. Its role in modulating prediction errors, deterring future neuron subtype. They discovered that
responses to rewards like food, sex, patronage. two dopamine neuron types tracked
money, or correct answers to ques- rewards and aversive events, while a
tions is well-known. Yet, a multitude Dopamine neurons convey reward third monitored movement, exempli-
of dopamine neuron types within the prediction errors to the brain through fied by the mice they studied when
brainstem’s uppermost region, each their firing patterns and dopamine they initiated faster locomotion.
producing dopamine, raises questions release, a mechanism facilitating
about potential variations in function. learning. Contemporary discussions on control-
ling dopamine’s effects predominantly
Recent research has unveiled an This firing occurs in two modes: revolve around the peak-and-valley
intriguing connection between dopa- phasic and tonic. Phasic firing entails release pattern. Yet, another mode
mine neuron types and their functions. rapid bursts, encoding reward predic- exists, where dopamine levels increase
Among these, a particular dopamine tion errors when unexpected rewards gradually until an awaited reward is
neuron type has surprised researchers, or surplus rewards are encountered. obtained, termed “ramping.” This
promising to reshape perceptions of Tonic firing represents steady, back- process, observed in the striatum,
this neurotransmitter for scientists, ground activity interspersed with reflects reward value and effort invest-
clinicians, and the public. phasic bursts. ment, essentially encoding motivation.
Dopamine’s claim to fame lies in its role However, dopamine’s functions extend While the mechanisms behind dopa-
in reward processing, a concept dating beyond reward prediction errors. mine ramping remain a topic of inves-
back decades. Dopamine neurons Recent studies have challenged the tigation, this unique release pattern
meticulously monitor the contrast notion that dopamine exclusively underlies goal pursuit and learning.
between expected and actual rewards, responds to rewards by revealing its Subsequent research into dopa-
termed a “reward prediction error.” responsiveness to aversive events. mine ramping holds the promise of
For example, dining at a new restau- Furthermore, research has identified enhancing our comprehension of moti-
rant with unknown quality serves as seven distinct dopamine neuron types vation and refining strategies for opti-
an arena for reward prediction errors. based on genetic profiles. mizing dopamine’s impact.
