The network of structures involved in emotion, motivation, and memory is the

The frontal lobes are the largest of the four lobes and are responsible for many different functions. The frontal lobes are considered our emotional control center and home to our personality. It's involved in motor function, problem solving, spontaneity, memory, language, initiation, judgment, impulse control, and social and sexual behavior. The frontal lobes are extremely vulnerable to injury due to their location at the front of the cranium, proximity to the sphenoid wing, and their large size.

The frontal lobes are located at the front of each cerebral hemisphere and positioned in front of or anterior to the parietal lobes and above and anterior to the temporal lobes. It's separated from the parietal lobe by the primary motor cortex, which controls voluntary movements of specific body parts associated with the precentral gyrus. The prefrontal cortex plays an important part in memory, intelligence, concentration, temper and personality.

The premotor cortex is a region found beside the primary motor cortex. It's involved in planning actions, along with the basal ganglia, and refining movements based upon sensory input. It guides eye and head movements and a person’s sense of orientation.

There are important asymmetrical differences in the frontal lobes. The left frontal lobe is involved in controlling language related movement, whereas the right frontal lobe plays a role in non-verbal abilities. The frontal lobes are also thought to play a part in spatial orientation.

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One of the most common effects of frontal damage can be a dramatic change in social behavior. A persons personality can undergo significant changes after an injury to the frontal lobes, especially when both lobes are involved. There are some differences in the left versus right frontal lobes in this area. Left frontal damage usually manifests as pseudodepression and right frontal damage as pseudopsychopathic.

It also controls motor skills such as voluntary and coordinated movement and speech. Broca's area, important in language production, is found in the frontal lobe, usually on the left side. Broca's area is next to the region that controls the movement of facial muscles, tongue, jaw and throat. If this area is damaged, a person will have difficulty producing the sounds of speech, because of the inability to move the tongue or facial muscles to form words. A person with Broca's aphasia can still read and understand spoken language, but has difficulty speaking and writing.

The parietal lobes interpret and integrate sensory information simultaneously from different modalities. It controls tactile sensation, response to internal stimuli, sensory comprehension, some language, reading, and some visual functions. This allows a person’s memory and the new sensory information received and gives meaning to objects, particularly determining spatial sense and navigation.

The occipital lobes are located at the back of the brain and enable humans to receive and process visual information. They influence how humans process colors and shapes. The occipital lobe on the right interprets visual signals from the left visual space, while the left occipital lobe performs the same function for the right visual space.

The temporal lobes are involved in auditory processing and are home to the primary auditory cortex. It's also involved in the processing of semantics in both speech and vision, plus some behavior. It also contains the hippocampus and plays a key role in the formation of long-term memory.

These lobes are located on each side of the brain at about ear level, and can be divided into two parts. One part is on the bottom ventral of each hemisphere, and the other part is on the side or lateral of each hemisphere. An area on the right side is involved in visual memory and helps humans recognize objects and peoples' faces. An area on the left side is involved in verbal memory and helps humans remember and understand language. The rear of the temporal lobe enables humans to interpret other people's emotions and reactions.

There's a region in the left temporal lobe called Wernicke's area. Damage to this area causes Wernicke's aphasia. An individual can make speech sounds, but they are receptive aphasia or meaningless because they don't make any sense.

The limbic system is a set of evolutionarily basic or primitive brain structures located on top of the brainstem and buried under the cortex. The limbic system is another subcortical structure that consists of structures and nerve fibers located deep within the cerebrum. This system connects the hypothalamus with other areas of the frontal and temporal lobes, including the amygdala and hippocampus.

Limbic system structures are involved in many of our emotions and motivations, particularly those that are related to survival. The limbic system controls the experience and expression of emotions, as well as some automatic functions of the body.

By producing emotions (such as fear, anger, pleasure, and sadness), the limbic system enables people to behave in ways that help them communicate and survive physical and psychologic upsets. The limbic system is also involved in feelings of pleasure that are related to our survival, such as those experienced from eating and sex.

The two large limbic system structures, the amygdala and hippocampus have important roles in memory.

The amygdala is responsible for determining what memories are stored and at what location in the brain. It's thought that this determination is based on how huge an emotional response an event invokes.

The hippocampus sends memories out to the appropriate part of the cerebral hemisphere for long-term storage and retrieves them when necessary. The hippocampus is also involved in the formation and retrieval of memories, and its connections through the limbic system help connect those memories to the emotions experienced when the memories form.

Damage to the amygdala or hippocampus may result in an inability to form new memories.

Part of the forebrain known as the diencephalon is also included in the limbic system. The diencephalon is located beneath the cerebral hemispheres and contains the thalamus and hypothalamus.

The thalamus is involved in sensory perception and regulation of motor functions. It connects areas of the cerebral cortex that are involved in sensory perception and movement with other parts of the brain and spinal cord that also have a role in sensation and movement. The hypothalamus is a very small but important component of the diencephalon. It plays a major role in regulating hormones, the pituitary gland, body temperature, the adrenal glands, and many other vital activities.

The thalamus is a relay and preprocessing station for the many nerve impulses that pass through it. Impulses carrying similar messages are grouped in the thalamus, then relayed to the appropriate brain areas.

The hypothalamus is the main neural control center in the brain that controls endocrine glands. The pituitary gland lies just below the hypothalamus and is a small endocrine gland that secretes a variety of hormones which are organic chemicals that regulate the body's physiological processes. When the hypothalamus detects certain body changes, it releases regulating factors or chemicals that stimulate or inhibit the pituitary gland. The pituitary gland then releases or blocks various hormones. Because of this close association between the nervous and endocrine systems, together they are called the neuroendocrine system.

The hypothalamus also regulates visceral or organ-related activities, food and fluid intake, sleep and wake patterns, sex drive, emotional states, and production of antidiuretic hormone (ADH) and oxytocin. The pituitary gland produces both these hormones.

The epithalamus is the most posterior or back portion of the diencephalon. It contains a vascular network involved in cerebrospinal fluid production. Extending from the epithalamus posteriorly is the pineal body, or pineal gland. Its function is thought to control body rhythms.