Key Questions Answered
Q: What is the main purpose of neuroscience?
A: At its most basic, neuroscience is the study of the nervous system – from structure to function, development to degeneration, in health and in disease. It covers the whole nervous system, with a primary focus on the brain.
Q: How many main parts of the brain are there?
A: The 3 main parts of the human brain are the cerebrum, cerebellum, and brainstem. See Image. Human Brain, Encephalon. The cerebrum is the largest part of the brain, divided into the right and left hemispheres.
Q: What are the three main areas of neuroscience?
A: Developmental neuroscience describes how the brain forms, grows, and changes. Cognitive neuroscience is about how the brain creates and controls thought, language, problem-solving, and memory. Molecular and cellular neuroscience explores the genes, proteins, and other molecules that guide how neurons function.
Q: What are the 7 main brain networks?
A: Depending on the granularity of how a network is defined, there is no single number of brain networks but at the highest level, the brain can be thought to consist of seven main networks – sensorimotor system, visual system, limbic system, central executive network (CEN), default mode network (DMN), salience network
Neuroscience is the scientific study of the nervous system. It is a multidisciplinary field that combines insights from biology, psychology, and medicine. It consists of several sub-disciplines, ranging from the study of neurochemicals to behavior and thought.
For example, cognitive neuroscience is the scientific study of the effects of: Brain structure Brain scanning techniques such as fMRI are used to conduct studies of mental processes.
What is Cognitive Neuroscience?
Cognitive neuroscience seeks to understand how the brain’s structure affects information processing and connects mental functions to particular brain regions. This is achieved through brain imaging methods like fMRI and PET scans.
The earliest historical roots of neuroscience can be found in the ancient Egyptians, who performed trepanation, a surgical procedure to drill holes in the skull to treat brain and/or mental illnesses, and had some knowledge of the symptoms of brain injury (Mohamed, 2008).
Much later, in the late 1890s, the invention of the microscope and the use of staining techniques led to the discovery of individual neurons by Santiago Ramón y Cajal, which laid the foundation for modern nervous system research (Guillery, 2004). Neuroscience emerged as a distinct field in the 20th century, pioneered by David Rioch, Francis O Schmitt and Stephen Kuffler (Cowan et al., 2000)
Noted that many branches of neuroscience are mainly categorized according to the analytical scales or viewpoints used to study the nervous system.
The molecules of the nervous system form the basis of neural function and communication, which is central to molecular neuroscience.
These molecular processes generate larger-scale cellular functions within neurons (e.g., neural signaling), which is a key area of research in cellular neuroscience. These functions enable complex communication systems between neurons, which is a key area of research in systems neuroscience.
Finally, these systems ultimately underlie thought and behavior, which is the focus of cognitive and behavioral neuroscience.
The scientific study of the nervous system is an essential branch of psychology because it provides important insights into how the mind and brain work.
Neuroscience helps us understand the various ways in which the mind functions through a network of neural connections, just as a computer functions through electrical connections.
By studying how these neural connections work, we can better understand common human cognition and disease—when these neural connections go wrong.
Key Facts
- The brain is the body’s most intricate and complex organ.
- Neurons communicate using both electrical and chemical signals.
- Genetically determined circuits are the basis of the nervous system.
- Life experiences change the nervous system.
- Intelligence occurs when the brain reasons, plans, and solves problems.
- The brain allows knowledge to be transmitted through language.
- The human brain drives our innate curiosity to comprehend how the world works.
- Fundamental discoveries advance healthy living and the treatment of disease.
Neurons and Synapses
Neurons are the fundamental cells of the nervous system, with roughly 100 billion present in the human body. Each neuron generally includes a cell body (soma), dendrites, and an axon.
The cell body contains the cell’s nucleus (where DNA is stored) and produces proteins necessary for neuron function.
Dendrites are branch-like structures that extend from the cell body and connect to other neurons to receive and process electrical signals. Finally, an axon extends from the opposite end of the cell body to generate and transmit electrical signals to other neurons.
Each neuron typically contains only one axon, but the structure may branch after initially projecting from the cell body (Woodruff, 2019).
Neurons function as electrical units, generating and transmitting signals known as action potentials. These electrical signals travel along the axon and are received by the dendrites of another neuron. Neurons have specialized channels that allow positively and negatively charged ions (cations and anions) to move in and out of the cell. This movement creates an electrical potential across the cell membrane, which is the outer boundary of the neuron.
Essentially (when a neuron is “resting”), the inside of the cell has a more negative charge than the outside, generating a resting membrane potential of -70 millivolts. However, this potential is constantly changing due to inputs from other cells, causing ions to flow in and out of the cell.
Some of these inputs are “excitatory,” meaning they make the cell’s membrane potential less negative (e.g., they allow cations to flow into the cell), while other inputs are “inhibitory,” meaning they make the cell’s membrane potential more negative.
If a neuron receives enough excitatory input and not too much inhibitory input, the membrane potential will exceed a value known as the “action potential threshold” (approximately -50 millivolts) to trigger an action potential.
Electrically, an action potential is a brief but dramatic spike in a neuron’s membrane potential. Neuroscientists often refer to action potentials simply as “spikes.”
When the membrane potential of a neuron exceeds the action potential limit, voltage-gated sodium channels open, allowing positively charged sodium ions to pass into the cell.
This causes a sudden increase in the cell membrane potential, generating a spike. This signal is rapidly transmitted along the neuron axon, as the spike itself can also open lower voltage-gated sodium channels. The process is then repeated.
Finally, when the action potential arrives at the end of the axon, the neuron passes the signal on to the next neuron.
Neurons communicate with each other through the following structures: synapse A synapse consists of a presynaptic terminal, a synaptic cleft, and a postsynaptic terminal.
When an action potential reaches the axon terminal of a neuron, it reaches the presynaptic terminal and causes neurotransmitters to be released from the cell. Neurotransmitters are released into the synaptic gap. there is a small (20–40 nm) spacing between the presynaptic and postsynaptic terminals.
Neurotransmitters cross the synaptic cleft and activate neurotransmitter receptors on the postsynaptic neuron terminal, which then allow cations or anions to flow into the postsynaptic neuron, causing excitation or inhibition, respectively.
When neurotransmitters act on receptors and cations flow into the postsynaptic neuron, the neuron approaches its action potential threshold, increasing the likelihood of firing, a process known as excitation.
Conversely, when a neurotransmitter acts on a receptor to allow anions to flow into the postsynaptic neuron, this is called inhibition because it moves the neuron.
As a result, some neurotransmitters are called excitatory neurotransmitters (because they induce excitement when they act on receptors), and others are called inhibitory neurotransmitters.
Common excitatory neurotransmitters include glutamate and dopamine, while common inhibitory neurotransmitters include GABA and glycine. One example of a neurotransmitter is serotonin, which can act as either excitatory or inhibitory, depending on the specific type of receptor it binds to.
Nervous system
Our nervous system is made up of billions of neurons, each firing action potentials and communicating with each other through synapses.
These neuronal networks ultimately form larger structures that perform specialized functions. By studying the anatomy of the nervous system, we can understand how it shares multiple functions.
The most important anatomical divisions of the nervous system are the central nervous system and the peripheral nervous system. Central Nervous System (CNS) – Composed of the brain and spinal cord, it serves as the main control center for the body.
Peripheral Nervous System (PNS) – Consists of nerves spread throughout the body that transmit information to and from the central nervous system. The central and peripheral nervous systems work together to interpret sensory information and initiate movement (Sukel, 2019). Sensory information is transmitted from the peripheral nerves to the spinal cord and then to the brain, and motor information is transmitted from the brain to the spinal cord and then via the peripheral nerves to the muscles.
Brain stem, the cerebellum and Cerebral cortex The brainstem primarily controls so-called “autonomic” functions, which means bodily functions that are controlled unconsciously, like heart rate and breathing. The cerebellum, located next to the brainstem, controls balance and coordination.
Finally, the cerebral cortex, located above the brainstem and cerebellum, is the part that most people think of when they think of the brain. The cerebral cortex is responsible for the sensory and cognitive functions that make up our mental lives (Sukel, 2019).
The cerebral cortex is separated into two hemispheres and four lobes. These hemispheres are connected by the corpus callosum, a bundle of nerve fibers that facilitates communication between the left and right sides. Despite common misconceptions, most cognitive functions involve both hemispheres working together. In other words, the right hemisphere is not more “creative” and the left hemisphere more “analytical.” One exception, however, is that most neural structures related to language reside in the left hemisphere (Sukel, 2019).
The cerebral cortex is split into two hemispheres and further divided into four distinct lobes. laryngeal lobe, temporal lobe, parietal lobe, and frontal lobe The occipital lobe is located at the back of the brain and is primarily responsible for visual processing.
Abstract
That’s all temporal lobe Located behind the forehead Guanzi play, it primarily covers speech information (including language) and some aspects of memory.
Parietal lobe is Situated above the ears, it is mainly responsible for interpreting sensory data, including touch and spatial orientation. Finally, the frontal lobe (the largest lobe) is located in front of the cortex above the eyes and is responsible for higher-level cognitive functions such as reasoning, decision-making, and planning.
The highly developed human frontal cortex is thought to distinguish humans from their primate ancestors (Sukel, 2019).
Each lobe contains gray matter and white matter Gray matter appears gray and is made up of neuron cell bodies, dendrites, and supporting cells.
The white color appears due to myelin, a fatty substance that surrounds the axon, allowing it to send signals more efficiently (Sukel, 2019).
The brain has many smaller areas that perform more specific functions. The main areas are:
- Awards bottom- It is the center that controls autonomic functions such as body temperature and blood pressure, and behaviors such as abdominal pain, thirst, and sexual desire.
- pituitary gland- It is connected to the hypothalamus and regulates the endocrine system by releasing hormones related to sexual development, bone and muscle growth, and stress.
- award — It is the main “relay station” that regulates information coming from the cerebral cortex.
- Basal ganglia – Collaborates with the cerebellum to regulate and refine accurate motor movements.
- Amygdala – Plays a key role in processing emotional reactions to various stimuli.
- Hippocampus – Essential for the formation and storage of long-term memories (“Anatomy,” 2018).
