Neurons called the brain and nervous system building blocks, are specialized cells that transmit information throughout the body. Their unique structure and ability to communicate with each other through electrical and chemical signals enable the vast array of human behaviors, thoughts, and emotions.

Structure and Function: A typical neuron comprises a cell body (soma), dendrites, and an axon. The cell body contains the nucleus and cytoplasm, essential for the neuron’s metabolic activities. Dendrites extend from the cell body like branches, receiving signals from other neurons. The axon is a long, thin projection that transmits these signals away from the cell body to other neurons, muscles, or glands.

How Neurons Develop: Neuronal development is a complex process that includes neurogenesis (the birth of neurons), differentiation (where neurons acquire their specific functions), and synaptogenesis (the formation of synapses). This process is guided by both genetic programming and environmental factors, allowing the nervous system to adapt to its surroundings. During development, neurons extend axons to reach their target cells and establish synaptic connections, a process involving guidance cues and signalling molecules.

Mirror Neurons: A fascinating subset of neurons, known as mirror neurons, was first discovered in the early 1990s. These neurons fire when an individual acts and when they observe the same action performed by another. Mirror neurons play a crucial role in understanding others’ actions, intentions, and emotions, contributing to developing empathy, social learning, and language acquisition.

Neural Communication: Neurons communicate at synapses, where one neuron’s axon terminal meets another’s dendrite. This communication is achieved by releasing neurotransmitters, chemical messengers that cross the synaptic gap and bind to receptors on the receiving neuron. This process converts the electrical signal into a chemical signal and back into an electrical signal in the receiving neuron, allowing the message to continue.

Neuroplasticity: One of the most remarkable aspects of neurons is their plasticity—their ability to change in response to experience or injury. Neuroplasticity manifests in several ways, including forming new connections, strengthening or weakening existing connections, and creating new neurons in some brain regions, even into adulthood. This adaptability is essential for learning, memory, and recovery from brain injuries.

In conclusion, neurons are not just the functional units of the brain and nervous system; they are dynamic entities that play a crucial role in every aspect of human thought, behavior, and emotion. The study of neurons, including specialized types like mirror neurons, continues to unravel the mysteries of the brain, offering insights into the fundamental processes that make us who we are.

Videos

Imaging reveals patterns in neuron firing

Description: In the brain, cortical neurons fire in response to stimuli from the body, and thalamic neurons provide feedback that regulates the cortical neurons’ firing―and thus helps keep the brain functioning smoothly. To find out more about the interplay between these two types of neurons, researchers in the Brain Mechanisms for Behavior Unit grew them in a dish from embryonic neurons.

Whole-brain Imaging of Neuronal Activity with Cellular Resolution

Video of dorsal and lateral projections of whole-brain, neuron-level functional activity in a zebrafish, reported by the genetically encoded calcium indicator GCaMP5G. HHMI Bulletin article: https://www.hhmi.org/bulletin/spring-2013/flashes-insight Nature: http://www.nature.com/nmeth/journal/v10/n5/full/nmeth.2434.html

Neurons under microscope

Uploaded by Mr.Duncan’s Social Studies Channel on 2019-02-11.

This is what brain cell conversations look like

Call them the neuron whisperers. Researchers are eavesdropping on conversations going on between brain cells in a dish. Rather than hearing the chatter, they watch neurons that have been genetically modified so that the electrical impulses moving along their branched tendrils cause sparkles of red light (see video).

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Neuronal Uniqueness in Neurodivergent Brains

Neurodivergence encompasses a wide range of neurological differences, including autism spectrum disorder (ASD), attention deficit hyperactivity disorder (ADHD), dyslexia, and others. Brain structure and function variations, including unique aspects of neuronal development, organization, and connectivity, characterize these conditions. While individual experiences and symptoms can vary widely, research has identified several neurobiological distinctions that contribute to the unique cognitive and sensory processing patterns observed in neurodivergent individuals.

Neuronal Development and Connectivity:

• Increased Synaptic Density: Neurodivergent brains, particularly in autism, have been observed to exhibit increased synaptic density, meaning there are more connections between neurons. This can lead to a more prosperous, albeit more overwhelming, sensory experience and may contribute to the enhanced detail-focused processing seen in some autistic individuals.
• Altered Neural Pathways: Differences in the development of neural pathways, including those related to social cognition, executive function, and sensory processing, have been documented. For example, in dyslexia, there is often altered connectivity in regions involved in reading and language processing. In ADHD, alterations in pathways associated with attention and executive functions are common.
• Mirror Neuron System Variations: The mirror neuron system, implicated in understanding others’ actions and intentions, shows differences in neurodivergent individuals, particularly those with autism. This variation may contribute to challenges in social interaction and empathy experienced by some people on the autism spectrum.

Neuroplasticity and Compensation:

Neurodivergent brains often exhibit remarkable neuroplasticity, allowing individuals to develop unique strategies to navigate their environments and tasks. This adaptive capability can lead to exceptional abilities in certain areas, such as memory, art, computing, and pattern recognition.

Sensory Processing:

Neurodivergent individuals frequently experience atypical sensory processing, which may be related to differences in neuronal sensitivity and synaptic processing. This can result in hypersensitivities or hyposensitivities to sensory inputs like sound, light, and touch, profoundly affecting daily functioning and preferences.

Structural and Functional Differences:

It’s crucial to note that neurodivergence encompasses a broad spectrum of neurological variations, and the degree to which these characteristics manifest can vary greatly among individuals. Understanding these unique neuronal attributes in neurodivergent brains continues to evolve, underscoring the importance of personalized approaches in education, therapy, and support. This changing understanding also celebrates the diversity of human brains and the myriad ways they interpret and interact with the world.

• Variability in Brain Volume and Structure: Research has identified variations in overall brain volume and the size and structure of specific brain regions in neurodivergent individuals. For instance, early rapid brain growth followed by a levelling off has been observed in some children with autism.
• Differential Activation Patterns: Functional imaging studies have shown that neurodivergent individuals may use different brain regions compared to neurotypical individuals when performing the same tasks. These differences in brain activation patterns highlight the diverse ways the brain can accomplish cognitive and sensory processing.