Brain
The human brain is a relatively small organ, making up only 2% of our total body weight, but it's incredibly powerful, weighing about 1400 grams and containing 100 billion cells. While it's commonly associated with thought, memory, and consciousness, the brain also plays a crucial role in controlling body movements and processing visual and somatosensory information. Different areas of the brain, like the Sensory Cortex, Motor Cortex, and Visual and Auditory Cortex, work together in specialized systems.
Size and Weight:
The human brain is relatively small, constituting 2% of total body weight.
Weighs approximately 1400 grams.
Comprises 100 billion cells.
Functions:
Commonly associated with thought, memory, and consciousness.
Controls body movements.
Processes visual and somatosensory information.
Responsible for attention, consciousness, emotions, and sleep.
Brain interprets nerve impulses from receptors.
Ongoing Exploration:
Higher functions like thought and creativity are still being explored in terms of neural processing.
All activities-be they motor, cognitive, or emotional-are planned and initiated in the frontal lobe.
The Frontal lobe executes motor control. Area 44 and 4 of the dominant hemispheres are centers of motor speech. Broca's area (area 44) and contiguous cortex (area 4) of the dominant hemisphere are centers of motor speech and related functions of lips, tongue, larynx, and pharynx; bilateral lesions cause paralysis of articulation, phonation, and deglutition.
The medial-orbital gyri and anterior cingulate gyri (frontal part of the limbic system) take part in the control of respiration, blood pressure, peristalsis, and other autonomic functions. Area 8 is cocrned in turning eyes
Prefrontal areas initiate planned action and executive control of all mental operations.
The Temporal lone constitutes superior, middle and inferior temporal gyrus, lateral occipitotemporal, fusiform, lingual Parahippocampal, and hippocampal convolutions as well as the transverse gyri if Herschel. Physiological the temporal lobe seems to be the site where all sensory modalities are integrated into self awareness.
The Transverse Gyri of Heschel, located deep within the sylvian fissure constitutes the primary auditory receptive area.
Superior temporal lobe is concerned with acoustic aspects of language
Middle and inferior convolutions are concerned with visual discrimination.
Connections Massive fiber system from the striate and parastriate zones project to the inferior and medial parts of the lobes.
The temporal lobes are interconnected through the anterior commissure and middle part of corpus callosum.
The inferior (uncinate) fasciculus connects the anterior temporal and orbital frontal regions.
The arcuate fasciculus connects the posterosuperior temporal lobe to the motor cortex adn Broca's area.
The parietal lobe is one of the four major lobes of the brain, and it is located near the back and top of the brain, behind the frontal lobe and above the occipital lobe. It plays a crucial role in various sensory and motor functions, as well as in higher cognitive processes. Here are some key functions associated with the parietal lobe:
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Sensory Processing:
The parietal lobe is involved in processing and integrating sensory information from different parts of the body. It plays a central role in spatial awareness, perception of movement, and the integration of sensory input from the environment.
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Somatosensory Cortex:
The primary somatosensory cortex, located in the postcentral gyrus of the parietal lobe, is responsible for processing tactile information, such as touch, pressure, temperature, and pain. Different areas of this cortex correspond to different parts of the body.
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Spatial Processing:
The parietal lobe is crucial for spatial orientation and awareness. It helps individuals understand the position of their body in space and perceive the location of objects in the surrounding environment.
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Motor Control:
While the primary motor cortex in the frontal lobe is primarily responsible for initiating voluntary movements, the parietal lobe is involved in coordinating and planning these movements. It integrates sensory information to help execute purposeful and coordinated actions.
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Visual-Spatial Processing:
The parietal lobe, particularly the posterior parietal cortex, plays a role in visual-spatial processing. This involves the ability to perceive and interpret spatial relationships, as well as the location and movement of objects in the visual field.
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Attention and Awareness:
The parietal lobe is associated with attention and awareness. It helps direct attention to relevant stimuli and is involved in the awareness of one's body and surroundings.
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Integration of Information:
The parietal lobe integrates information from different sensory modalities, allowing for a cohesive perception of the external world. It contributes to the formation of a unified sensory experience.
Damage or dysfunction in the parietal lobe can result in various neurological symptoms, such as sensory deficits, difficulties with spatial orientation, impaired motor control, and disturbances in visual-spatial processing. The specific effects depend on the location and extent of the damage. Understanding the functions of the parietal lobe provides insights into how the brain processes sensory information and enables us to interact effectively with our environment.