Our nervous system is a complex mechanism for the interaction of neurons that send impulses to the brain, and it, in turn, controls all organs and ensures their work. This process of interaction is possible due to the presence in humans of the main inseparable acquired and innate forms of adaptation - conditional and unconditional reactions. A reflex is a conscious response of the body to certain conditions or stimuli. Such well-coordinated work of nerve endings helps us interact with the outside world. A person is born with a set of simple skills - this is called An example of such behavior: the ability of an infant to suck on its mother's breast, swallow food, blink.
and animal
As soon as a living being is born, he needs certain skills that will help ensure his life. The body actively adapts to the surrounding world, that is, it develops a whole range of purposeful motor skills. This mechanism is called species behavior. Each living organism has its own set of reactions and innate reflexes, which is inherited and does not change throughout life. But the behavior itself is distinguished by the method of its implementation and application in life: congenital and acquired forms.
Unconditioned reflexes
Scientists say that an innate form of behavior is an unconditioned reflex. An example of such manifestations has been observed since the birth of a person: sneezing, coughing, swallowing saliva, blinking. The transfer of such information is carried out by inheritance of the parent program by centers that are responsible for reactions to stimuli. These centers are located in the brain stem or spinal cord. Unconditioned reflexes help a person quickly and accurately respond to changes in the external environment and homeostasis. Such reactions have a clear demarcation depending on biological needs.
- Food.
- Approximate.
- Protective.
- Sexual.
Depending on the species, living beings have different reactions to the world around them, but all mammals, including humans, have a sucking skill. If you attach an infant or a young animal to the mother's nipple, a reaction will immediately occur in the brain and the feeding process will begin. This is the unconditioned reflex. Examples of eating behavior are inherited in all creatures that receive nutrients from mother's milk.
Defense reactions
These types of reactions to external stimuli are inherited and are called natural instincts. Evolution has laid in us the need to protect ourselves and take care of our safety in order to survive. Therefore, we have learned to instinctively respond to danger, this is an unconditioned reflex. Example: Have you noticed how the head deviates if someone raises a fist over it? When you touch a hot surface, your hand withdraws. This behavior is also called hardly a person in their right mind will try to jump from a height or eat unfamiliar berries in the forest. The brain immediately starts the process of processing information that will make it clear whether it is worth risking your life. And even if it seems to you that you don’t even think about it, the instinct immediately works.
Try to bring your finger to the baby's palm, and he will immediately try to grab it. Such reflexes have been developed over the centuries, however, now such a skill is not really needed by a child. Even among primitive people, the baby clung to the mother, and so she endured him. There are also unconscious innate reactions, which are explained by the connection of several groups of neurons. For example, if you hit the knee with a hammer, it will twitch - an example of a two-neuron reflex. In this case, two neurons come into contact and send a signal to the brain, causing it to respond to an external stimulus.
Delayed reactions
However, not all unconditioned reflexes appear immediately after birth. Some arise as needed. For example, a newborn baby practically does not know how to navigate in space, but after about a couple of weeks he begins to react to external stimuli - this is an unconditioned reflex. Example: the child begins to distinguish the voice of the mother, loud sounds, bright colors. All these factors attract his attention - an indicative skill begins to form. Involuntary attention is the starting point in the formation of the assessment of stimuli: the baby begins to understand that when the mother speaks to him and approaches him, most likely she will take him in her arms or feed him. That is, a person forms a complex form of behavior. His crying will draw attention to him, and he uses this reaction consciously.
sexual reflex
But this reflex belongs to the unconscious and unconditioned, it is aimed at procreation. It occurs during puberty, that is, only when the body is ready for procreation. Scientists say that this reflex is one of the strongest, it determines the complex behavior of a living organism and subsequently triggers the instinct to protect its offspring. Despite the fact that all these reactions are inherently human, they are launched in a certain order.
Conditioned reflexes
In addition to the instinctive reactions that we have at birth, a person needs many other skills in order to better adapt to the world around him. Acquired behavior is formed both in animals and in humans throughout life, this phenomenon is called "conditioned reflexes". Examples: at the sight of food, salivation occurs, while observing the diet, there is a feeling of hunger at a certain time of the day. Such a phenomenon is formed by a temporary connection between the center or vision) and the center of the unconditioned reflex. An external stimulus becomes a signal for a certain action. Visual images, sounds, smells are able to form stable connections and give rise to new reflexes. When someone sees a lemon, salivation may begin, and with a sharp smell or contemplation of an unpleasant picture, nausea occurs - these are examples of conditioned reflexes in humans. Note that these reactions can be individual for each living organism, temporary connections are formed in the cerebral cortex and send a signal when an external stimulus occurs.
Throughout life, conditioned responses can come and go. Everything depends on For example, in childhood, a child reacts to the sight of a bottle of milk, realizing that this is food. But when the baby grows up, this object will not form an image of food for him, he will react to a spoon and a plate.
Heredity
As we have already found out, unconditioned reflexes are inherited in every species of living beings. But conditioned reactions affect only the complex behavior of a person, but are not transmitted to descendants. Each organism "adjusts" to a particular situation and the reality surrounding it. Examples of innate reflexes that do not disappear throughout life: eating, swallowing, reaction to the taste of the product. Conditioned stimuli change constantly depending on our preferences and age: in childhood, at the sight of a toy, the baby experiences joyful emotions; in the process of growing up, the reaction is caused, for example, by visual images of a film.
Animal reactions
Animals, like humans, have both unconditioned innate reactions and acquired reflexes throughout their lives. In addition to the instinct of self-preservation and the production of food, living beings also adapt to the environment. They develop a reaction to the nickname (pets), with repeated repetition, an attention reflex appears.
Numerous experiments have shown that it is possible to instill in a pet many reactions to external stimuli. For example, if at each feeding you call the dog with a bell or a certain signal, he will have a strong perception of the situation, and he will immediately react. In the process of training, rewarding a pet for an executed command with a favorite treat forms a conditioned reaction, walking a dog and the type of leash signals an imminent walk where he should relieve himself are examples of reflexes in animals.
Summary
The nervous system constantly sends a lot of signals to our brain, they form the behavior of humans and animals. The constant activity of neurons allows us to perform habitual actions and respond to external stimuli, helping to better adapt to the world around us.
