Page 1 :
Second Semester B.Sc. Psychology- PSY2C01: Human Physiology –Nervous System, , FUNCTIONS OF THE BRAIN AREAS, The cerebral cortex is a sheet of neural tissue that is outer most to the cerebrum, of the brain. The cortex is composed of three parts: sensory, motor, and association, areas. Sensory areas of the brain receive and process sensory information, including, sight, touch, taste, smell, and hearing. The motor areas, arranged like a pair of, headphones across both cortex hemispheres, are involved in the control of voluntary, movements. Association areas of the cortex integrate current states with past states to, predict proper responses based on sets of stimuli., Association areas, Association areas produce a meaningful perceptual experience of the world. It, enable human to interact effectively, and support abstract thinking and language. The, parietal, temporal, and occipital lobes, all located in the posterior part of the cortex,, organize sensory information into a clear model of our environment centered on our, body image. The frontal lobe or prefrontal association complex is involved in planning, actions and movement, as well as thought., In humans the association areas are the most developed part of the cerebral, cortex, and the brain in general. These areas are necessary for perceptual activities, like, recognizing objects, rather than simple outlines, edges or sensory qualities like colour, or pitch. They are so called because they receive and analyse signals simultaneously, from multiple regions of both the motor and sensory cortices as well as from subcortical, structures. The most important association areas are, 1. Parieto-occipito temporal association area, 2. Prefrontal association area., 3. Limbic association area., 1. Parieto-occipito temporal association area, This association area lies in the large parietal and occipital cortical space in the, cerebral cortex. This area is bounded by the somatosensory cortex anteriorly and the, visual cortex posteriorly lateral side of this area lays the auditory cortex. This area, provides a high level of interpretative meaning for signals from all the surrounding, sensory areas. This area has many functional sub areas., Dr. Shibu Abdullah, Department of Psychology, Amal College of Advanced Studies, NIlambur, , 1

Page 2 :
Second Semester B.Sc. Psychology- PSY2C01: Human Physiology –Nervous System, , A. Area for the analysis of the Spatial Coordinates of the Body., It is an area extending from the posterior parietal cortex to the superior occipital, cortex. It provides continuous analysis of the spatial coordinates of all parts of the body, as well as of the surroundings of the body. This area receives visual sensory information, from the posterior occipital cortex and simultaneous somatosensory information from, the anterior parietal cortex. From all this information, it computes the coordinates of, the visual, auditory, and body surroundings., B. Area for Language Comprehension:, It is the major area for language comprehension. All intellectual functions are, language based. It is the most important region of the entire brain for higher intellectual, functions. Language comprehension area is called Wernicke’s area and it lies behind the, primary auditory cortex of the brain., Wernicke’s area, Wernicke’s area is the major area for language comprehension. It is the most, important region of the entire brain for higher intellectual functions. This area was first, described in 1874 by German neurologist Carl Wernicke. This area is very important for, the comprehension of speech sounds and is considered to be the receptive language, or, language comprehension, centre. It lies close to the auditory cortex. Wernicke's area is, usually located in the back part of the temporal lobe. The exact location can vary. It is, most frequently found in the left hemisphere of the brain, but not always., Aphasia is an impairment of language, which affects an individual's ability to, understand and produce both spoken and written communication. When Wernicke's, area of the brain is damaged, a disorder known as Wernicke's aphasia can result., Wernicke's aphasia is a language disorder that impacts language comprehension and, the production of meaningful language due to damage to the Wernicke's area of the, brain. In some cases this condition is referred to as fluent aphasia, sensory aphasia, or, receptive aphasia. According to the National Aphasia Association, people with, Wernicke's aphasia can frequently produce speech that sounds normal and, grammatically correct. The actual content of this speech makes little sense. Non-existent, and irrelevant words are often included in the sentences that these individuals produce., C. Area for Initial Processing of Visual Language (Reading):, Dr. Shibu Abdullah, Department of Psychology, Amal College of Advanced Studies, NIlambur, , 2

Page 3 :
Second Semester B.Sc. Psychology- PSY2C01: Human Physiology –Nervous System, , The Visual association area is lying mainly in the anterolateral region of the, occipital lobe. It is seen posterior to the language comprehension area. For instance,, when we read books, visual information conveyed by words will be directed by visual, association area into Wernicke’s area. This area is needed to make meaning out of the, visually perceived words. In its absence, a person can still have excellent language, comprehension through hearing but not through reading., D. Area for Naming Objects, This area is seen in the most lateral portions of the anterior occipital lobe and, posterior temporal lobe. The names are learned mainly through auditory input, whereas, the physical natures of the objects are learned mainly through visual input. In turn, the, names are essential for both auditory and visual language comprehension. It may be, noted that functions performed in Wernicke’s area are located immediately superior to, the auditory “names” region and anterior to the visual word processing area., 2. Prefrontal association area, This area lies in the front part of the frontal lobe of the cortex. The prefrontal, association area functions in close association with the motor cortex to plan complex, patterns and sequences of motor movements. This area receives strong input from a, subcortical bundle of nerve fibres which connecting the parieto-occipitotemporal, association area with the prefrontal association area. By this, the prefrontal cortex, receives pre-analyzed sensory information on the spatial coordinates of the body that is, necessary for planning effective movements. Output signals from the prefrontal area, into the motor control system passes through the caudate portion of the basal gangliathalamic circuit for motor planning, which provides many of the sequential and parallel, movement stimulation. The prefrontal association area is also essential to carrying out, “thought” processes in the mind. Prefrontal area can process non-motor as well as, motor information from different areas of the brain for non-motor types of thinking as, well as motor types., Broca’s area, This area is located in the frontal part of the left hemisphere of the brain. It is, discovered in 1861 by French surgeon Paul Broca. It is otherwise known as convolution, of Broca. This area contains neurons involved in speech function and serves a vital role, Dr. Shibu Abdullah, Department of Psychology, Amal College of Advanced Studies, NIlambur, , 3

Page 4 :
Second Semester B.Sc. Psychology- PSY2C01: Human Physiology –Nervous System, , in the generation of articulate speech. The function of Broca’s area is to help to put, words together fluently to speak more than one word at a time, forming complete, sentences. The Broca’s area lies specifically in the third frontal convolution, just anterior, to the face area of the motor cortex. The Broca’s area is connected to other regions of, the brain, including the Wernicke area, by a neuronal tract known as the arcuate, fasciculus. In addition to serving a role in speech production, the Broca’s area also is, involved in language comprehension in motor-related activities associated with hand, movements, and in sensorimotor learning and integration., Damage to the frontal lobe can result in a speech disorder known as Broca, aphasia. It is characterized by careful, brief speech with very simple grammatical, structure, though the speaker may be quite clear as to what he or she wishes to say and, may communicate successfully. Broca's aphasia is the result of damage to a specific, language region in the frontal lobe of the brain. Broca’s aphasia, like other types of, aphasia, is most common after a stroke affecting Broca's area, but it can result from, Infection of the brain, head injury, dementia, brain tumour etc. Some people who have, Broca's aphasia experience a degree of recovery without treatment or therapy. Usually,, speech exercises and tailored therapy sessions are beneficial because your ability to, understand and cooperate is not affected by Broca's aphasia., 3. Limbic Association Area, This area is found in the anterior pole of the temporal lobe, in the ventral portion, of the frontal lobe, and in the cingulate gyrus lying deep in the longitudinal fissure on, the mid-surface of each cerebral hemisphere. It is concerned primarily with behavior,, emotions, and motivation. The limbic association area receives information from, virtually every other association area and therefore can relate all the stimuli of an event,, including its emotional context. The emotion associated with an event can determine, whether or how long it is remembered. This is important for survival of all organisms., Indeed, this is what is meant by learning. You can’t have learning without memory., , Dr. Shibu Abdullah, Department of Psychology, Amal College of Advanced Studies, NIlambur, , 4