Name: spinal cord nerves and reflexes
Uploaded: 2024-08-29T22:13:37.000Z
Duration: 1 min 26 s
Channel: JoVE

K12 Standards

Florida Department of Education

High School

Life Science

SC.912.L.14

SC.912.L.14.28

Spinal Cord

The spinal cord begins at the base of the brain and extends down the middle of the back, serving as a vital communication link between the brain and the body.
The spinal cord is divided into several segments, eight cervical, twelve thoracic, five lumbar, five sacral, and one coccygeal segment. Nerves arising from the spinal cord connect to specific body parts through the peripheral nervous system.
There are three types of nerve cells in the spinal cord: sensory neurons, motor neurons, and interneurons.&#160;
Sensory neurons transmit sensory information to the spinal cord, while motor neurons send information from the spinal cord to glands and muscles. Interneurons connect sensory and motor neurons and constitute most of the spinal cord&#39;s structure.
Additionally, the spinal cord can initiate reflex actions without input from the brain.
For instance, when an individual touches a hot pan, a sensory neuron in the skin detects the pain and sends the signal to the spinal cord. The input is immediately processed by an interneuron, which triggers a motor neuron that quickly prompts the muscles to pull the hand away.

spinal cord

The spinal cord, a critical component of the central nervous system, extends from the base of the brainstem to the lumbar region of the vertebral column. It is essential for maintaining physical stability and facilitating communication between the brain and peripheral parts of the body.
<ul>
	<li>&#8226; Encased within the protective bony structure of the spine, the spinal cord is divided into 30 segments that correspond to the vertebrae.</li>
	<li>&#8226; These segments play a vital role in connecting specific body regions through a vast network of nerves, allowing for a bidirectional flow of information crucial for various bodily functions.</li>
	<li>&#8226; Each spinal segment connects to a specific part of the body through paired spinal nerves, which are categorized into &#8212; cervical, thoracic, lumbar, sacral, and coccygeal regions based on their location along the vertebral column.</li>
	<li>&#8226; These nerves exit the spinal cord through spaces between the vertebrae, transmitting sensory and motor information.</li>
</ul>
The spinal cord consists of three primary types of nerve cells: sensory neurons, motor neurons, and interneurons.
<ul>
	<li>&#8226; Sensory neurons are pivotal in conveying information about external stimuli from sensory receptors to the spinal cord. This information includes sensations such as touch, temperature, and pain.</li>
	<li>&#8226; Interneurons, the most numerous within the spinal structure, process and integrate this sensory information. They act as intermediaries, enabling communication between sensory and motor neurons and facilitating the coordination of appropriate motor responses.</li>
	<li>&#8226; Motor neurons transmit impulses from the spinal cord to the body&#39;s muscles and glands, initiating and controlling all voluntary movements and many involuntary actions. This underscores the spinal cord&#39;s integral role in motor function.</li>
</ul>
A notable function of the spinal cord is its ability to coordinate reflex actions independently of the brain. Reflex arcs are neural circuits that activate directly in response to sensory inputs to produce immediate reactions. For instance, upon touching a hot surface, sensory neurons quickly send a signal to the spinal cord. Interneurons immediately process this information and activate motor neurons, resulting in the rapid withdrawal of the hand. This reflex action occurs to protect the body from harm and highlights the spinal cord&#39;s complex functionality and its critical role in the human body&#39;s operational hierarchy.

The spinal cord begins at the base of the brain and extends down the middle of the back, serving as a vital communication link between the brain and the ...

Education

JoVE Core

Introduction to Psychology

Unit 1

Biopsychology

KEY TERMS AND CONCEPTS

spinal cord nerves and reflexes

The spinal cord is a major part of the central nervous system. It runs from the base of the brainstem to the lumbar region of the vertebral column. It helps keep the body stable and carries signals between the brain and the rest of the body.

The spinal cord sits inside the bony spine for protection. It is divided into 30 segments that match the vertebrae. Each segment connects to a specific body region through paired spinal nerves.

These spinal nerves are grouped by where they leave the vertebral column. The regions are cervical, thoracic, lumbar, sacral, and coccygeal. They exit through spaces between the vertebrae and carry sensory and motor information.

The spinal cord contains three main types of nerve cells. Sensory neurons bring information from sensory receptors to the spinal cord. This includes touch, temperature, and pain.

Interneurons are the most numerous nerve cells in the spinal cord. They process and combine sensory input. They also link sensory neurons to motor neurons so the body can respond in the right way.

Motor neurons send signals from the spinal cord to muscles and glands. They control voluntary movement and many involuntary actions. The spinal cord also handles reflex arcs, which are fast neural pathways that work without direct brain control.

A reflex arc can protect the body from harm. When a person touches a hot surface, sensory neurons send a signal to the spinal cord. Interneurons process the message and activate motor neurons, which make the hand pull away quickly.

Spinal Cord Nerves and Reflexes

introduction to biological bases of psychology

introduction-to-biological-bases-of-psychology

Biological Factors Shaping Behavior and Mind

Biopsychology connects biology and psychology by showing how the body influences behavior and mental processes. It focuses on the nervous system, neurotransmitters, hormones, genetics, and evolutionary ideas. Together, these areas help explain why people think, feel, and act the way they do. The nervous system is the main foundation of biopsychology. It has two parts: the central nervous system, or CNS, and the peripheral nervous system, or PNS. The CNS includes the brain and spinal cord and...

nervous system

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neurons as communicators of the brain

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cerebral hemispheres

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The spinal cord is a major part of the central nervous system. It runs from the base of the brainstem to the lumbar region of the vertebral column. It helps keep the body stable and carries signals between the brain and the rest of the body. The spinal cord sits inside the bony spine for protection. It is divided into 30 segments that match the vertebrae. Each segment connects to a specific body region through paired spinal nerves. These spinal nerves are grouped by where they leave the...

lateralization

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human genetics

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genetic variation

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behavioral genetics and its designs

How Behavior Genetics Studies Inheritance

Behavior genetics studies how inherited genes influence human behavior. It looks at how genes passed from parents to offspring help shape behavioral traits and tendencies. The field also examines how inherited factors and environmental influences work together. Researchers use family studies, twin studies, and adoption studies to separate genetic and environmental effects. Family studies track traits within biological families to find possible genetic patterns. They have helped identify...

evolutionary psychology

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Evolutionary psychology explains human behavior and mental processes through natural selection. It uses Darwin’s idea that traits can spread when they help survival and reproduction. In this view, some common behaviors may be adaptations that were useful to our ancestors. One clear example is fear of snakes. This fear is nearly universal, which suggests that early humans who avoided snakes were more likely to survive deadly encounters. Over many generations, that caution could be passed on and...

organization of the brain

Brain Regions and Their Key Functions

The brain is the main control center of the nervous system. It processes sensory input, makes decisions, and directs body actions. Its structure is divided into the hindbrain, midbrain, and forebrain, and each part supports important functions. The hindbrain sits at the base of the brain. It helps regulate automatic life processes. The medulla oblongata controls involuntary functions such as heartbeat, breathing, and blood pressure. Nearby, the pons acts as a bridge between brain regions,...

neuroplasticity

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somatosensory, motor, and association cortex

somatosensory-motor-and-association-cortex

Brain Cortex Areas for Sensation and Movement

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the endocrine system

Endocrine Glands and Hormone Signals

The endocrine system is a network of glands that send hormone signals through the body. Hormones are chemical messengers that help control many body functions. They enter the bloodstream and travel to cells with the right receptors, or target sites, so the signal can be received. Because of this, hormone effects are widespread, unlike the more localized effects of neurotransmitters. This signaling helps the body keep a stable internal environment, called homeostasis. Several major glands...

major hormones and their functions

Hormone Imbalances and Their Effects

Hormones are chemical messengers made by endocrine glands. They help control body functions and keep internal conditions stable. When hormone levels shift too far up or down, normal body processes can be disrupted. Several major hormones have clear roles in the body. Oxytocin is made in the hypothalamus and released by the pituitary gland. It supports social bonding, childbirth, and lactation. Low oxytocin can affect social interaction and stress response, and it may contribute to depression.

inheritance

Genes, Traits, and Mendel's Rules

Genes, traits, and Mendel's rules explain how characteristics pass from parents to offspring. Gregor Mendel's pea plant experiments changed how scientists understand heredity. His work showed that traits are controlled by discrete units inside organisms called genes. Genes usually come in pairs. One gene is inherited from each parent, and together they make a person's genotype. Genotype is the genetic blueprint for potential traits. Examples include blood type, eye color, and inherited...

gene-environment interactions

How Environment Shapes Gene Expression

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heritability

Heritability and the Environment

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natural selection and adaptation

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Natural selection and mating preferences work together to shape how organisms survive and reproduce. Natural selection favors traits that help an organism fit its environment. Mating preferences are part of sexual selection, which influences who mates with whom and how genes are passed on. Evolutionary psychologists argue that these preferences are tied to instincts that support reproduction. For females, conception, pregnancy, and nursing create a strong need to choose mates who can offer...

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Social Learning vs. Evolutionary Psychology

Social learning theory and evolutionary psychology offer two different ways to explain sexual behavior. A study in which strangers gave students compliments and then asked for casual sex showed a clear gender gap. None of the women said yes, while 70% of the men agreed. Evolutionary psychology explains this result by arguing that natural selection may have shaped women to be more selective about sexual partners. From this view, selectivity can help improve survival and reproductive success. It...

key terms and concepts

Explore how spinal cord segments, spinal nerves, and nerve cells work together to relay signals, control movement, and trigger fast reflexes.

Spinal Cord Nerves and Reflexes | JoVE K12

JoVE Core Introduction to Psychology offers an engaging learning experience on the fundamental principles of psychology through concise video lessons. Students will explore important topics such as cognitive processes, emotional regulation, and neural mechanisms, establishing a strong foundation in the study of the mind and human behavior. This series provides an accessible and captivating approach to grasp the essential concepts of the discipline.

introduction to psychology

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SC.912.L.14.4

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Spinal Cord Nerves and Reflexes

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