Author: Alice Ferng B.S., MD, PhD • Reviewer: Dimitrios Mytilinaios MD, PhD Show
Originally defined and numbered into 52 regions by the German anatomist Korbinian Brodmann in the early 1900’s, the Brodmann areas of the cerebral cortex are defined by its cytoarchitecture (histological structure and cellular organization). It is important to remember that the same Brodmann area numbers in humans and primates often do not translate to other species. In addition, these Brodmann areas have been widely redefined, discussed, debated, and refined exhaustively based on cytoarchitecture, cortical functions, and brain plasticity. Key facts about Brodmann areas
This article will discuss the Brodmann areas and their function. Contents
+ Show all Anatomical basisThe Brodmann areas were initially based on the cytoarchitectural organization of neurons in the cerebral cortex. Specifically, it was observed that they were organized in distinct groups once the cells were stained using the Nissl method (which consists of basic dyes, notably staining the rough endoplasmic reticulum—also known as Nissl substance—dark blue). Many of these areas of distinct neuronal organization have since been correlated to various cortical functions. Since there are 52 distinct Brodmann regions, only a few of the major regions will be further elaborated in this article. However, a list of all areas defined can be found below for reference. Neuroanatomy is big topic, so it's important to start with a solid foundation. Have you already mastered the basics? Our free diagrams and quizzes on the parts of the brain are a great place to get started. Important Brodmann areasAreas 1,2,3Primary somatosensory cortex (or Postcentral gyrus) – this is numbered rostral to caudal as 3,1,2. This region is associated with several senses, such as the ones for:
Area 4This are is also known as the primary motor cortex (or Precentral gyrus) (may possibly include part of Area 6). It is responsible for executing motor movements, which includes contralateral finger/hand/wrist or orofacial movements, learned motor sequences, breathing control, and voluntary blinking. Precentral gyrus (cross section)Area 5Somatosensory association cortex – Brodmann area 5 is part of the parietal cortex. Associated functions include:
Area 6Premotor and Supplementary Motor Cortex – this region is critical for the sensory guidance of movement and control of proximal and trunk muscles, and contributes to the planning of complex and coordinated motor movements. This area plays a large role in motor, language, and memory functions, including:
Note: The “Motor Association Cortex” includes areas 6, 8, 44, and 45. This association cortex is involved in movement throughout the body, including motor speech movements. Area 9Dorsolateral/anterior prefrontal cortex (DLPFC) – This region is the highest cortical area responsible for motor planning, organization, and regulation, and sustaining attention and working memory. The DLPFC plays an important role in:
In sum, all complex mental activities require crosstalk between cortical and subcortical circuits that are connected to the DLPFC. Area 10Anterior prefrontal cortex – involved in strategic processes of memory retrieval and executive functions, such as
There is a significant role of Areas 9 and 10 in memory encoding and retrieval, and area 10 is thought to control and manipulate event and time-based prospective memory (metamemory), and allow “intentional forgetting.” Area 10 is also involved in attending to sensory stimulation and use of language (generating sentences, word-stem completion, verbal fluency, syntactic processing, and metaphor comprehension). Area 17Primary visual cortex (V1) – the visual cortex is located in the occipital lobe in the back of the brain, and contains a well-defined map of the spatial information required for vision. Area 22Primary auditory cortex / Superior Temporal Gyrus (part of Wernicke’s area) – this region is situated close to the external ear and involves complex language and auditory processing. Area 37Fusiform Gyrus / Occipitotemporal Gyrus – this region is largely involved in:
Areas 22, 39, 40Wernicke’s area – the gyri that comprise this area may be larger or smaller in different people and itis responsible for speech fluency. More precisely, this area allows you to string words together in complete and sensical sentences. An easy way to temember is to think of “Wordy Wernicke”. Areas 44,45Broca’s area – this region is associated with the praxis of speech (motor speech programming). This includes:
You can remember it by thinking of “Broken boca” where boca means ‘mouth’ in Spanish. All Brodmann areas
(*) Area only found in non-human primates. Dive into our Brodmann area quiz and test your knowledge! Lesions of Brodmann areasAreas 1,2,3A lesion in this area would cause:
Area 4A lesion in this area would cause paralysis of the contralateral side of the body, including facial palsy, arm or leg monoparesis, and hemiparesis. Area 5A lesion in the left superior parietal lobe would cause ideomotor apraxia, which is the loss of ability to produce purposeful, skilled movements as a result of brain pathology not due to physical weakness, paralysis, lack of coordination or sensory loss. Astereognosis (also known as tactile agnosia) is also possible, which would lead to loss of ability to recognize objects by feeling or handling them. Area 6A lesion here would affect sensory guidance of movement and control of proximal and trunk muscles. Damage of the lateral premotor area would result in kinetic apraxia (which would appear as coarse or unrefined movements that no longer have the appearance of being practiced over time). Other lesions would cause loss of other functional processes described. Area 9A lesion in the DLPFC will create difficulties in inhibiting responses and result in dysexecution syndrome, which leads to problems with affect, social judgement, executive memory, abstract thinking, and intentionality. Area 10A lesion here is similar to what would be seen in Area 9, since the two areas are associated. Area 17Depending on where and how damage and lesions occur to this region, partial or complete cortical blindness can result; for example, if the upper bank of the calcarine sulcus is damaged, then the lower bank of the visual field is affected. Area 22Lesions in this area results in:
Areas 22, 39, 40A lesion here causes language disorders characterized by fluent speech paraphasias where a lot of words are jumbled and nonsensical sentences are spoken. There may also be language comprehension deficits. Areas 44, 45Lesions in this area cause Broca’s aphasia: a deficit in the ability to speak and produce the proper words/sounds, even though the afflicted person maintains the ability to comprehend language and to mentally formulate proper sentences. SourcesAll content published on Kenhub is reviewed by medical and anatomy experts. The information we provide is grounded on academic literature and peer-reviewed research. Kenhub does not provide medical advice. You can learn more about our content creation and review standards by reading our content quality guidelines. References:
Illustrators:
Brodmann areas: want to learn more about it? Our engaging videos, interactive quizzes, in-depth articles and HD atlas are here to get you top results faster. What do you prefer to learn with? “I would honestly say that Kenhub cut my study time in half.” – Read more. Kim Bengochea, Regis University, Denver © Unless stated otherwise, all content, including illustrations are exclusive property of Kenhub GmbH, and are protected by German and international copyright laws. All rights reserved.Which brain lobe is responsible for voluntary movement thinking personality and intentionality or purpose?The frontal lobes are important for voluntary movement, expressive language and for managing higher level executive functions.
What brain lobe is responsible for registering spatial location attention and motor control?Located above the occipital lobe and behind the frontal lobe, the parietal lobe plays a key role in sensory perception and integration, including spatial reasoning and your sense of your body's movement within the world.
What structure is responsible for 80% of the brain volume and is critical to perception thinking and language?The preponderance of the cerebral cortex (which, with its supporting structures, makes up approximately 80 percent of the brain's total volume) is actually a recent development in the course of evolution.
Which brain lobe is predominantly responsible for hearing language processing and memory?The temporal lobe is located on the side of the head (temporal means “near the temples”), and is associated with hearing, memory, emotion, and some aspects of language. The auditory cortex , the main area responsible for processing auditory information, is located within the temporal lobe.
|