**Abstract**

Insecticides are pesticides used to control insects in agriculture, ornamental gardens, homes, and veterinary medicine. Although the toxic effects on the environment and the health of living beings are not fully understood, these pesticides have become the first options for crop protection in agriculture. After herbicides, insecticides are the most extensively used pesticides in agriculture, with large quantities consumed on every continent, primarily in America. Chlorpyrifos, carbaryl, and imidacloprid are among the top ten most used insecticides. Amidst organophosphates, chlorpyrifos has been reported to be used in over fifty food crops. Carbaryl is a carbamate employed as an insecticide, fungicide, herbicide, and nematicide. Similarly, neonicotinoids are the most used insecticide on a global scale. Neonicotinoids include imidacloprid, the second most frequently used pesticide, surpassed only by glyphosate. It is used because it is less toxic to humans. However, insects appear to be less resistant to its compounds. Evidence suggests that these insecticides persist in soils for a long time and have neurotoxic effects in animal species not intended to receive its consequences. Thus, this chapter's aim is to describe these three pesticides effects and contrast them with the most recent findings regarding their neurotoxic effects in various animal species.

**Keywords:** insecticides, chlorpyrifos, carbaryl, imidacloprid, neurotoxicity
