Wernicke’s Area: Location and Function

Wernicke’s area is a structure of the brain discovered by Carl Wernicke that is believed to be involved in language comprehension, specifically the comprehension of speech sounds. It is also considered to be the receptive language center of the brain.

Location

Wernicke’s area is typically located in the dominant hemisphere of the brain—usually the left cerebral hemisphere for right-handed individuals and many left-handed people.

More specifically, it lies within the posterior portion of the superior temporal gyrus, a ridge of brain tissue involved in auditory processing.

This region corresponds to Brodmann area 22, which plays a key role in language comprehension.

As part of the temporal lobe, Wernicke’s area is positioned near the junction where the temporal lobe meets the parietal and occipital lobes, close to the lateral sulcus.

Wernicke’s Area Vs Broca’s Area

Wernicke’s area and Broca’s area are crucial for language but they serve distinct functions.

Wernicke’s area, located in the posterior part of the temporal lobe, is primarily responsible for language comprehension. It helps us understand both spoken and written language.

Broca’s area, found in the frontal lobe, is essential for speech production. It enables us to form words and construct grammatically correct sentences.

Damage to Wernicke’s area typically results in fluent but nonsensical speech with impaired comprehension, while damage to Broca’s area leads to halting, effortful speech with intact understanding.

How They Work Together

Broca’s and Wernicke’s areas are connected by the arcuate fasciculus (a bundle of nerve fibers that links language comprehension and production areas).

When we hear speech, Wernicke’s area interprets it and sends the message to Broca’s area, which helps us respond clearly and fluently. This connection enables smooth, meaningful conversation.

Function

Wernicke’s area plays a crucial role in how we understand language. It works as part of a larger network that processes what we hear and read, transforming sounds and symbols into meaning.

Below are five key functions it supports:

• Recognizing Speech Sounds
  In partnership with the auditory cortex, Wernicke’s area helps identify and organize the sounds of speech. This early stage involves detecting phonemes and matching them to known word patterns, allowing the brain to recognize that a sequence of sounds is, for example, the word “banana.”

• Speech Comprehension
  Once sounds are identified as words, Wernicke’s area interprets their meaning within context. This function allows us to understand full sentences, grasp implied meaning, and follow conversations—even when language is rapid or informal.

• Semantic Processing
  Wernicke’s area plays a central role in semantic processing—the ability to link words to their meanings and relationships. It helps us distinguish between similar words (like “book” and “notebook”) and understand language nuances, metaphors, or double meanings.

• Written Language Understanding
  Beyond spoken words, Wernicke’s area contributes to reading comprehension. When we read, it helps convert written symbols into meaningful language, allowing us to understand everything from short texts to complex articles.

• Language Integration and Monitoring
  Wernicke’s area helps coordinate with other brain regions—especially Broca’s area—to support fluid language use. It may also assist in monitoring our own speech for accuracy, forming part of a feedback loop that lets us detect and correct mistakes in real time.

Historical Context:

Initially, Broca's and Wernicke's areas were seen as distinct centers for speech production and comprehension respectively. 

Wernicke’s area would choose which words are needed for speech, while Broca’s area is responsible for taking these words and generating the movements needed to vocalize them.

The Wernicke-Geschwind model later proposed a network connecting these areas. Modern neuroscience, however, reveals a more complex, distributed language system. 

Wernicke's area, once thought to be solely responsible for language comprehension, is now understood as part of a broader language network, interacting with multiple brain regions for various language functions.

Damage

Carl Wernicke discovered that damage to the posterior region of the superior temporal gyrus resulted in a distinct type of aphasia.

While Broca’s aphasia is characterized by non-fluent, effortful speech with preserved comprehension, Wernicke’s patients exhibited fluent speech but significant comprehension difficulties.

Symptoms of Wernicke’s aphasia include:

• Fluent but disordered speech
• Impaired understanding of spoken language
• Difficulty with silent reading comprehension
• Use of inappropriate or nonsensical words (paraphasias)
• Creation of new, meaningless words (neologisms)
• Unawareness of their own speech errors
• Inability to repeat words or phrases accurately
• Normal speech rhythm and intonation despite content errors

The understanding of damage to Wernicke’s area has been refined over the years. The exact location and extent of damage leading to Wernicke’s aphasia can vary, suggesting a more distributed language network.

Isolated damage to Wernicke’s area that spares underlying white matter may not always cause severe receptive aphasia (DeWitt & Rauschecker, 2013).

Likewise, some patients with lesions in classical Wernicke’s area have shown relatively intact word comprehension, indicating other regions may also contribute to this function (DeWitt & Rauschecker, 2013).

This highlights the complexity of language processing in the brain and the ongoing refinement of our understanding of Wernicke’s area and its associated aphasia.

Discovery

Around the time of Wernicke’s Area discovery, neuroscientists were trying to understand a new perspective of the brain.

Few suggested that the cerebral hemispheres of the brain were not equal in terms of function and that the left hemisphere performed different roles than the right hemisphere and vice versa.

Through post-mortem examinations, Broca discovered that there was damage to an area in the left hemisphere in these individuals, which is named Broca’s area.

A few years after Broca, German neurologist Carl Wernicke, who was said to be heavily inspired by Broca, found a similar problem with speech in some of his patients.

However, the issues with these patients differed from Broca’s patients as they could produce speech but could not comprehend language. These individuals would speak fluently but with disordered speech, impaired understanding of speech, and impaired silent reading.

When examining the brains of these patients, it was discovered that there was a lesion at the junction of the parietal, temporal, and occipital lobes in the left cerebral hemisphere, which he coined Wernicke’s Area.

How Did This Discovery Impact Psychology?

Wernicke’s discovery had a profound impact on the field of psychology, particularly in advancing the concept of lateralization of brain functions.

By identifying a specific area in the left hemisphere crucial for language comprehension, Wernicke provided strong evidence against the then-prevalent holistic view of brain function.

This work, along with Broca’s earlier findings, was instrumental in establishing the idea that different cognitive functions are localized to specific brain regions, predominantly in one hemisphere.

Wernicke’s contribution thus played a key role in shaping our understanding of the brain’s functional organization and laid the groundwork for modern neurolinguistics.