For most people, sexual arousal is a combination of physical and cognitive reactions to erotic stimuli. It can include physiological activation, such as an increase in heart rate and blood pressure.
fMRI studies have shown that various brain regions are activated during the arousal, desire, arousal, and orgasm phases of human sexual response. Some of these brain areas are discussed below.
The Hypothalamus
The hypothalamus is a cluster of nuclei that connects the nervous and endocrine systems. It sits in the lower brainstem and is visible on coronal or horizontal sections of the brain. Its rostrocaudal and dorso-ventral zones form its superior boundaries, while the tuberal region forms the inferior boundary. The hypothalamus has eleven major nuclei – This information is the byproduct of the portal’s rigorous analysis sexxxnet.com.
Neuroscientists are still learning a lot about this area of the brain. They are interested in how it regulates sexual arousal, and they also study its effects on other emotions. The hypothalamus is also involved in the fight-or-flight response and in learning new cues. It is important for maintaining homeostasis, and it controls many of the body’s essential functions.
There is a theory that the neural circuitry in this brain region is able to activate multiple parts of the brain at once. It is believed that this may be what allows us to experience a full range of feelings at once.
In addition to stimulating the endocrine system, it is thought that the hypothalamus stimulates and inhibits several other body processes. These include hormone release, water intake, temperature regulation, and other basic functions. For example, the hypothalamus releases thyrotropin-releasing hormones to regulate the thyroid gland and to control body weight. It also releases gonadotropin releasing hormones to stimulate the pituitary gland to release reproductive hormones.
The Pituitary Gland
The pituitary gland (hypophysis cerebri) is a small hormone-producing gland that sits in the sella turcica, a small hollow space in the base of your skull underneath your brain and in front of the bridge of your nose. It is a specialized neuroendocrine gland that secretes a variety of important hormones that directly control other endocrine glands and many body functions.
The anterior pituitary lobe, the larger of the two lobes, contains hormone-secreting epithelial cells and is connected to your hypothalamus through blood vessels. The hypothalamus controls the anterior pituitary lobe by secreting’releasing hormones’ that induce or suppress hormone release from the gland depending on your body needs.
Four of the hormones secreted by the anterior pituitary lobe directly regulate other endocrine glands. These hormones include thyroid-stimulating hormone (TSH), adrenocorticotropic hormone (ACTH), follicle stimulating hormone and luteinizing hormone. These hormones in turn control the production of estrogen and progesterone by your ovaries and sperm in men, and the production of eggs in women. They also regulate your sleep patterns by producing the hormone melatonin.
The posterior pituitary gland, which is smaller than the anterior lobe, contains a group of nerve endings that are actually part of your brain. These nerve endings, which originate in the hypothalamus, elicit’releasing hormones’ that cause your pituitary to secrete oxytocin and vasopressin. These hormones are then stored in the posterior pituitary gland for later release.
The Parabrachial Nucleus
The parabrachial nucleus is a set of neurons that relay noxious sensory stimuli, such as pain and threatening noises, to forebrain structures that respond to them. They are critical to both responding to threatening stimuli and learning to avoid them. Recent techniques such as optogenetics allow direct manipulation of individual neurons and associated pathways. These tools are being used to delineate critical circuits and establish their role in mediating threat responses.
Neuroimaging studies have shown that sexual arousal is directed by the hypothalamus, which governs desire, lubrication and erection; the amygdala, which processes emotions; the prefrontal cortex, which makes decisions; the cerebellum, which controls motor response; and the parietal lobes, which process sensory information. They have also revealed that the brainstem is involved in promoting arousal and regulating heart rate and respiration.
Research suggests that the occipital lobe detects sexual visual stimuli, such as a low-cut dress or T-shirt that marks the biceps, and transmits signals to the parietal lobe, where we recognize what arouses us. The ventromedial prefrontal cortex, which is connected to these regions through a variety of circuits, promotes the recognition and grading of sexually attractive stimuli.
The parabrachial nucleus (PB) is a subnuclear structure in the dorsolateral pons, surrounding the superior cerebellar peduncle. It consists of 13 distinct subdivisions including the lateral parabrachial nucleus (LPBN), medial parabrachial nucleus (MPBN) and the ventrolateral Kolliker-Fuse nucleus (vKFN). Each has its own projection patterns to other regions of the brain. The vKFN and LPBN have extensive connections with the amygdala, while the external and extreme lateral PB nuclei project to the bed nucleus of the stria terminalis and associated parts of the substantia innominata.
The Nucleus Accumbens
The nucleus accumbens is part of a group of subcortical brain structures called the basal ganglia. It is the neural interface between motivation and action and plays a key role in feeding, sexual, reward, stress-related, and drug self-administration behaviors. This area is also responsible for addiction, and is involved in a number of mental health disorders including depression, bipolar disorder, obsessive-compulsive disorder, and anxiety disorders.
This area is made up of a cluster of neurons known as the medium spiny neurons (MSN). These neurons have various behavioral phenotypes, ranging from quasi-inhibitory, using the inhibitory neurotransmitter GABA, to primarily excitatory, using the excitatory neurotransmitter glutamate. It is this combination of neural activity that allows the nucleus accumbens to function as a reward system.
The nucleus accumbens has been shown to be divided into two functionally distinct regions, Shell and Core. The Shell region has a strong connection to the limbic system and the prefrontal cortex. It acts as a “coincidences detector” and activates during behavior with an adaptive value, reinforcing goal-directed motor sequences mediated by the core region and pyramidal and extrapyramidal motor systems. The Core region has a strong connection to the substantia nigra and the motor cortex. It sends signals of reinforcement to the pyramidal and extrapyramidal motors, enhancing motivation and reward-seeking behavior. This area also receives information about upcoming rewards from other brain regions such as the hippocampus and the amygdalae.
Leave a Comment