Systems neuroscience is a subdiscipline of
neuroscience
Neuroscience is the scientific study of the nervous system (the brain, spinal cord, and peripheral nervous system), its functions, and its disorders. It is a multidisciplinary science that combines physiology, anatomy, molecular biology, ...
and
systems biology
Systems biology is the computational modeling, computational and mathematical analysis and modeling of complex biological systems. It is a biology-based interdisciplinary field of study that focuses on complex interactions within biological system ...
that studies the structure and function of various neural circuits and systems that make up the central nervous system of an organism.
Systems neuroscience encompasses a number of areas of study concerned with how
nerve cells
A neuron (American English), neurone (British English), or nerve cell, is an excitable cell that fires electric signals called action potentials across a neural network in the nervous system. They are located in the nervous system and help to ...
behave when connected together to form
neural pathway
In neuroanatomy, a neural pathway is the connection formed by axons that project from neurons to make synapses onto neurons in another location, to enable neurotransmission (the sending of a signal from one region of the nervous system to ano ...
s,
neural circuits, and larger
brain networks. At this level of analysis, neuroscientists study how different neural circuits work together to analyze sensory information, form perceptions of the external world, form emotions, make decisions, and execute movements.
Researchers in systems neuroscience are concerned with the relation between
molecular
A molecule is a group of two or more atoms that are held together by attractive forces known as chemical bonds; depending on context, the term may or may not include ions that satisfy this criterion. In quantum physics, organic chemistry, ...
and
cellular approaches to understanding brain structure and function, as well as with the study of high-level mental functions such as
language
Language is a structured system of communication that consists of grammar and vocabulary. It is the primary means by which humans convey meaning, both in spoken and signed language, signed forms, and may also be conveyed through writing syste ...
,
memory
Memory is the faculty of the mind by which data or information is encoded, stored, and retrieved when needed. It is the retention of information over time for the purpose of influencing future action. If past events could not be remembe ...
, and
self-awareness
In philosophy of self, philosophy, self-awareness is the awareness and reflection of one's own personality or individuality, including traits, feelings, and behaviors. It is not to be confused with consciousness in the sense of qualia. While ...
(which are the purview of
behavioral
Behavior (American English) or behaviour (British English) is the range of actions of individuals, organisms, systems or artificial entities in some environment. These systems can include other systems or organisms as well as the inanimate p ...
and
cognitive
Cognition is the "mental action or process of acquiring knowledge and understanding through thought, experience, and the senses". It encompasses all aspects of intellectual functions and processes such as: perception, attention, thought, ...
neuroscience). To deepen their understanding of these relations and understanding, systems neuroscientists typically employ techniques for understanding networks of neurons as they are seen to function, by way of
using either
single-unit recording or multi-electrode recording,
functional magnetic resonance imaging
Functional magnetic resonance imaging or functional MRI (fMRI) measures brain activity by detecting changes associated with blood flow. This technique relies on the fact that cerebral blood flow and neuronal activation are coupled. When an area o ...
(fMRI), and
PET scans.
The term is commonly used in an educational framework: a common sequence of graduate school neuroscience courses consists of cellular/molecular neuroscience for the first semester, then systems neuroscience for the second semester. It is also sometimes used to distinguish a subdivision within a neuroscience department in a university.
Major branches
Systems neuroscience has three major branches in relation to measuring the brain: behavioral neuroscience, computational modeling, and brain activity. Through these three branches, it breaks down the core concepts of systems neuroscience and provides valuable information about how the functional systems of an organism interact independently and intertwined with one another.
Behavioral neuroscience
Behavioral neuroscience
Behavioral neuroscience, also known as biological psychology, biopsychology, or psychobiology,[Psychobi ...](_blank)
in relation to systems neuroscience focuses on representational dissimilarity matrices (RDMs), which categorizes brain activity patterns and compares them across different conditions, such as the dissimilar level of brain activity observing an animal in comparison to an inanimate object. These models give a quantitative representation of behavior while providing comparable models of the patterns observed.
5 Correlations or anticorrelations between brain-activity patterns are used during experimental conditions to distinguish the processing of each brain region when stimuli is presented.
Computational modeling
Computational models
A computational model uses computer programs to simulate and study complex systems using an algorithmic or mechanistic approach and is widely used in a diverse range of fields spanning from physics, engineering, chemistry and biology to economics ...
provide a base form of brain-activity level, which is typically represented by the firing of a single neuron. This is essential for understanding systems neuroscience as it shows the physical changes that occur during functional changes in an organism. While these models are important for understanding brain-activity, one-to-one correspondence of
neuron firing has not been completely uncovered yet. Different measurements of the same activity lead to different patterns, when in theory, the patterns should be the same, or at least similar to one another. However, studies show fundamental differences when it comes to measuring the brain, and science strives to investigate this dissimilarity.
Brain activity
Brain activity and brain imaging help scientists understand the differences between functional systems of an organism in combination with computational models and the understanding of behavioral neuroscience. The three major branches of systems neuroscience work together to provide the most accurate information about brain activity as
neuroimaging
Neuroimaging is the use of quantitative (computational) techniques to study the neuroanatomy, structure and function of the central nervous system, developed as an objective way of scientifically studying the healthy human brain in a non-invasive ...
allows in its current state. While there can always be improvements to brain-activity measurements, typical imaging studies through electrophysiology can already provide massive amounts of information about the systems of an organism and how they may work intertwined with one another. For example, using the core branches of systems neuroscience, scientists have been able to dissect a migraine’s attack on the nervous system by observing brain-activity dissimilarities and using computational modeling to compare the differences of a functioning brain and a brain affected by a migraine.
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Observations
Systems neuroscience is observed through
, which focuses on the electrical activity of biological systems in an organism. Through electrophysiology studies, the activity levels of different systems in the body help explain abnormalities of systematic functioning, such as an abnormal heartbeat rhythm or a stroke. While the main focus of electrophysiology is the heart, it does provide informational scanning of brain activity in relation to other bodily functions, which can be useful for the connection of neurological activity between systems.
Although systems neuroscience is generally observed in relation to a human’s level of functioning, many studies have been conducted on
drosophila
''Drosophila'' (), from Ancient Greek δρόσος (''drósos''), meaning "dew", and φίλος (''phílos''), meaning "loving", is a genus of fly, belonging to the family Drosophilidae, whose members are often called "small fruit flies" or p ...
, or the small fruit fly, as it is considered to be easier due to the simpler brain structure and more controllable genetic and environmental factors from an experimental standpoint. While there are strong dissimilarities between the functioning capabilities of a fruit fly in comparison to a human, these studies still provide valuable insight on how a human brain might work.
Neural circuits and neuron firing is more easily observable in fruit flies through functional brain imaging, as neuronal pathways are simplified and, therefore, are easier to follow. These pathways may be simple, but by understanding the basis of neuron firing, this can lead to important studies on a human’s neuronal pathway and eventually to a one-to-one neuron correspondence when a system is functioning.
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See also
;Example systems
*
Ascending reticular activating system
*
Auditory system
The auditory system is the sensory system for the sense of hearing. It includes both the ear, sensory organs (the ears) and the auditory parts of the sensory system.
System overview
The outer ear funnels sound vibrations to the eardrum, incre ...
*
Gustatory system
The gustatory system or sense of taste is the sensory system that is partially responsible for the perception of taste. Taste is the perception stimulated when a substance in the mouth reacts chemically with taste receptor cells located on t ...
*
Motor system
The motor system is the set of central nervous system, central and peripheral nervous system, peripheral structures in the nervous system that support motor functions, i.e. movement. Peripheral structures may include skeletal muscles and Efferen ...
*
Olfactory system
The olfactory system, is the sensory nervous system, sensory system used for the sense of smell (olfaction). Olfaction is one of the special senses directly associated with specific organs. Most mammals and reptiles have a main olfactory system ...
*
Reward system
The reward system (the mesocorticolimbic circuit) is a group of neural structures responsible for incentive salience (i.e., "wanting"; desire or craving for a reward and motivation), associative learning (primarily positive reinforcement and c ...
*
Sensory system
The sensory nervous system is a part of the nervous system responsible for processing sensory information. A sensory system consists of sensory neurons (including the sensory receptor cells), neural pathways, and parts of the brain involved ...
*
Somatosensory system
The somatosensory system, or somatic sensory system is a subset of the sensory nervous system. The main functions of the somatosensory system are the perception of external stimuli, the perception of internal stimuli, and the regulation of bod ...
*
Visual system
The visual system is the physiological basis of visual perception (the ability to perception, detect and process light). The system detects, phototransduction, transduces and interprets information concerning light within the visible range to ...
;Related concepts
*
Sensory neuroscience
Sensory neuroscience is a subfield of neuroscience which explores the anatomy and physiology of neurons that are part of sensory systems such as vision, hearing, and olfaction. Neurons in sensory regions of the brain respond to stimuli by firi ...
*
Neural oscillation
*
Neural correlate
The neural correlates of consciousness (NCC) are the minimal set of neuronal events and mechanisms sufficient for the occurrence of the mental states to which they are related. Neuroscientists use empirical approaches to discover neural correla ...
*
Neural substrate
*
Behavioral neuroscience
Behavioral neuroscience, also known as biological psychology, biopsychology, or psychobiology,[Psychobi ...](_blank)
*
Neuroimaging
Neuroimaging is the use of quantitative (computational) techniques to study the neuroanatomy, structure and function of the central nervous system, developed as an objective way of scientifically studying the healthy human brain in a non-invasive ...
*
References
*3. Bear, M. F. et al. Eds. (1995). ''Neuroscience: Exploring The Brain''. Baltimore, Maryland, Williams and Wilkins.
*4. Hemmen J. L., Sejnowski T. J. (2006). ''23 Problems in Systems Neuroscience''. Oxford University Press.
*5. Kriegeskorte, N., Mur, M., & Bandettini, P. (2008). Representational similarity analysis - connecting the branches of systems neuroscience. ''Frontiers in Systems Neuroscience, 2'', 4–4.
https://doi.org/10.3389/neuro.06.004.2008
*6. Brennan, K. C., & Pietrobon, D. (2018). A Systems Neuroscience Approach to Migraine. ''Neuron (Cambridge, Mass.)'', ''97''(5), 1004–1021.
https://doi.org/10.1016/j.neuron.2018.01.029
*7. Kazama, H. (2015). Systems neuroscience in Drosophila : Conceptual and technical advantages. ''Neuroscience, 296,'' 3–14.
https://doi.org/10.1016/j.neuroscience.2014.06.035
{{Systems
Branches of neuroscience
Systems biology