Assignment Question
Think about a simple action you do regularly, like answering your phone, texting, turning on a light switch, …. When you perform this routine act, what are the individual neurons in your nervous system doing to make it possible? Write a 400-word paper that 1) describes the action (as it relates to observable behavior and the underlying mental processes), 2) summarizes the action potential and synaptic transmission involved in a standard neuron involved in this action, 3) explains which specific neurotransmitters are involved, and 4) discuss what parts of the central and/or peripheral nervous systems make the action possible.
Assignment Answer
Introduction
Everyday actions, such as answering a phone call or turning on a light switch, may seem simple, but beneath the surface lies a complex interplay of neurons and neurotransmitters that make these actions possible. This paper delves into the neural mechanisms involved in performing routine actions, specifically focusing on the action potential, synaptic transmission, neurotransmitters, and the central and peripheral nervous systems’ roles.
Describing the Action
Routine actions involve observable behaviors and underlying mental processes. Take answering a phone call, for example. When your phone rings, you reach for it, press a button, and begin speaking. These observable behaviors are driven by underlying mental processes, including sensory perception, decision-making, and motor control.
Action Potential and Synaptic Transmission
The neural basis of these actions starts with individual neurons. When you hear the phone ring, sensory neurons in your ear detect the sound waves and convert them into electrical signals. These signals travel as action potentials—a brief electrical impulse—along the length of the neuron’s axon.
At the synapse, where one neuron communicates with another, the action potential triggers the release of neurotransmitters into the synaptic cleft. In the case of auditory perception, glutamate is a key neurotransmitter. Glutamate binds to receptors on the receiving neuron, leading to the generation of a new action potential in the next neuron in the chain.
Neurotransmitters Involved
In the example of answering a phone call, several neurotransmitters play crucial roles:
- Glutamate: As mentioned, glutamate is the primary excitatory neurotransmitter involved in relaying auditory information from sensory neurons to the central nervous system. It initiates action potentials in postsynaptic neurons, allowing the signal to propagate.
- Acetylcholine: When you decide to answer the call and reach for the phone, acetylcholine is released to stimulate motor neurons, initiating the movement of your arm and fingers to pick up the phone.
- Dopamine: This neurotransmitter is involved in reward and motivation. When you successfully answer the call, your brain’s reward system releases dopamine, reinforcing the behavior and making you more likely to repeat it in the future.
Central and Peripheral Nervous Systems
To perform these routine actions, both the central and peripheral nervous systems are actively involved. The central nervous system, including the brain and spinal cord, processes sensory information, makes decisions, and coordinates motor responses. In the case of answering a phone call, the brain’s auditory cortex interprets the sound, and the motor cortex coordinates the physical response of reaching for the phone.
The peripheral nervous system consists of sensory and motor neurons that connect the central nervous system to the body’s periphery. Sensory neurons transmit information from sensory organs to the central nervous system, while motor neurons transmit signals from the central nervous system to muscles and glands. This intricate network enables the precise execution of everyday actions.
Conclusion
In conclusion, seemingly simple actions like answering a phone call involve a complex neural orchestra. From action potentials and synaptic transmission to neurotransmitters like glutamate, acetylcholine, and dopamine, every step is finely tuned to facilitate these actions. Both the central and peripheral nervous systems work in harmony to make these routine behaviors possible. Understanding the neuroscience behind everyday actions offers a deeper appreciation of the intricate workings of the human nervous system.
References
Bear, M. F., Connors, B. W., & Paradiso, M. A. (2016). Neuroscience: Exploring the Brain. Wolters Kluwer.
Purves, D., Augustine, G. J., Fitzpatrick, D., Katz, L. C., LaMantia, A. S., McNamara, J. O., & Williams, S. M. (2018). Neuroscience. Oxford University Press.
Kandel, E. R., Schwartz, J. H., Jessell, T. M., Siegelbaum, S. A., & Hudspeth, A. J. (2013). Principles of Neural Science. McGraw-Hill Education.
Shepherd, G. M. (2013). Neurobiology. Oxford University Press.
Herculano-Houzel, S. (2016). The Human Advantage: A New Understanding of How Our Brain Became Remarkable. MIT Press.
Frequently Asked Questions (FAQs)
1. What is an action potential, and how does it relate to routine actions like answering a phone call?
Answer: An action potential is a brief electrical impulse that travels along neurons. In routine actions, it serves as the means by which sensory information is transmitted to the brain and motor commands are sent to execute the action.
2. Which neurotransmitters are involved in decision-making when performing everyday actions?
Answer: Dopamine plays a crucial role in decision-making during routine actions. It is associated with the brain’s reward system and reinforces behaviors like answering a phone call when they lead to a favorable outcome.
3. How do sensory neurons contribute to routine actions like turning on a light switch?
Answer: Sensory neurons detect environmental stimuli, such as the need for light, and transmit this information to the central nervous system. This input informs the decision to perform actions like turning on a light switch.
4. What role does the central nervous system play in everyday actions like picking up a ringing phone?
Answer: The central nervous system, particularly the brain’s motor cortex, coordinates the physical response necessary for actions like reaching for and picking up a phone when it rings.
5. Can disruptions in neurotransmitter function affect our ability to perform routine actions?
Answer: Yes, disruptions in neurotransmitter function can impact routine actions. For instance, imbalances in dopamine can affect motivation and reward, potentially influencing the likelihood of performing certain actions. Neurological disorders that affect neurotransmitter levels can also impair routine actions.
