Frontal lobe Frontal lobe: the most advanced part of the developing brain, it includes the primary motor area, the premotor area and the prefrontal lobe. It is located in front of the central sulcus. Between the central sulcus and the precentral sulcus is the precentral gyrus. In front of it are the superior frontal sulcus and the inferior frontal sulcus, and between them are the superior frontal gyrus, the middle frontal gyrus and the inferior frontal gyrus. The posterior part of the inferior frontal gyrus has the ascending and horizontal branches of the lateral fissure divided into the orbital, triangular and lid parts. The anterior part of the frontal lobe is the frontal pole. The frontal lobe has a straight gyrus and an orbital gyrus bounded by an orbital sulcus on its base, and its innermost deep sulcus is the olfactory bundle sulcus, which houses the olfactory bundle and olfactory bulb. The olfactory bundle is divided posteriorly into medial and lateral olfactory striae. The triangle bounded by its bifurcation is called the olfactory triangle, also called the anterior perforating plenum, from which many perforating vessels of the anterior fundic artery ring enter the brain. On the medial side of the frontal lobe, the portion of the anterior and posterior central gyrus that continues is called the paracentral lobule. It is responsible for thinking, planning, and is associated with the needs and emotions of the individual. Together with the dorsomedial nucleus of the thalamus, the prefrontal lobe forms the perceptual system and is the most important site of mental activity. The function of the frontal lobes is to exchange output samples and to illuminate thalamic output awareness through the linkage pathway. The prefrontal lobe and the dorsomedial thalamic nucleus establish a linkage pathway through contact fibers, and it is through this linkage pathway that samples are lit up for thalamic awareness. Frontal Lobe Symptom Cluster The frontal lobe is located in the anterior part of the brain and has four major gyri, namely the precentral gyrus, superior frontal gyrus, middle frontal gyrus, and inferior frontal gyrus. Frontal lobe lesions mainly cause disorders of random movement, speech, cranial nerve, vegetative nerve function and mental activity. Etiology】 Frontal lobe symptoms can appear when cranial trauma affects the anterior cranial fossa, lesions of the branches from the anterior and middle cerebral arteries to the frontal lobe, sinus infection, frontal lobe tumor and pituitary stroke. Clinical manifestations】 1, cranial nerve palsy: in case of anterior cranial sulcus tumor or limited arachnoiditis, olfactory impairment on the focal side, primary optic nerve atrophy and contralateral optic papillary edema, bilateral optic papillary edema, vision on the diseased side can rapidly decrease or even disappear completely. 2.Motor disorders:frontal lobe irritative lesions, jerking of the contralateral upper and lower limbs or face-Jackson’s epilepsy; generalized grand mal seizures; paralytic seizures. 3. Abnormal reflexes: frontal lobe premotor area lesion, contralateral strong grip reflex, groping reflex, canine reflex and early contralateral tonic reflex, contralateral upper limb Leri’s reflex. 4, frontal ataxia: frontal lobe lesions, half of the patients in the area appear sitting, walking disorders, turning instability, easy to lean to the opposite side of the lesion. 5, motor aphasia: complete motor aphasia, the patient completely lost the ability to speak, but the articulation and tongue motor muscle can be good; partial motor aphasia, the patient can issue a certain speech, but the vocabulary is poor, slow speech, grammatical errors, often say the wrong thing. 6.Phytokinetic dysfunction: heart rate, blood pressure changes and gastrointestinal dysfunction. 7. Mental disorders: early appearing near memory impairment, no memory is still preserved. As the lesion progresses, distant memory is lost, and indifferent expression and inattention appear. Mood fluctuation, sexual impulsiveness, excitement, irritability are the characteristics of frontal lobe lesions. 8. Dysgraphia, defiant disorder, and lignocardia: The patient is unable to dictate and write automatically, i.e., inability to write. There is resistance to any action imposed on the patient, i.e. defiant disorder. The patient does not eat or speak, his facial expression is often fixed, and he does not respond to internal or external stimuli. This state can last for hours, weeks, or months.