Superior Temporal Gyrus & Wernicke

Anatomy

• Heschl’s gyrus (transverse temporal gyrus, BA 41–42): primary auditory cortex, deep in the Sylvian fissure.
• Wernicke’s area: posterior STG (BA 22), planum temporale (usually larger on the left).
• Superior temporal sulcus (STS): a social perception region.
• Blood supply: inferior division of the MCA.

Functions

• Auditory perception (tonotopic map), sound recognition.
• Decoding speech sounds (phonemes) and grasping word meaning (Wernicke).
• Right: inferring emotion from music, tone of voice and prosody.
• STS: perception of biological motion, gaze direction and facial expression dynamics; voice–face integration.

Connections and chemistry

• Thalamus — medial geniculate body (auditory input)
• Broca’s area (arcuate fasciculus)
• Amygdala (emotional value of sound)
• Fusiform face area (social perception with the STS)

Development

Developmental course through childhood and adolescence.

• Specialization for the sounds of the native language within the first year (6–12 months, perceptual narrowing).
• Myelination of auditory pathways is completed in early childhood; the STS social perception network develops in childhood.

Clinical

• ASD: reduced STS response to the human voice (Gervais et al., 2004), differences in biological motion processing.
• Early-onset schizophrenia: STG activation during auditory hallucinations, reduced STG volume.
• Developmental language disorder, auditory processing disorder, dyslexia (phonological).
• Landau-Kleffner syndrome: acquired aphasia due to temporal epileptiform activity.

Treatment

This region from the perspective of medication, psychotherapy and neuromodulation. Letter badges are evidence levels.

• Landau-Kleffner syndrome: corticosteroids and antiepileptic drugs to suppress epileptiform activity; early treatment matters for language recovery. Speech and language therapy, sign language if needed. C
• Auditory hallucinations in early-onset schizophrenia: antipsychotic treatment; clozapine in resistant cases (including adolescents). CBT for voices and relating-to-the-voice (avatar) therapies are promising in adults. A
• Speech and language therapy for auditory processing and language difficulties; an FM system and noise reduction in the classroom. C

Assessment

Neuropsychological tasks and measures that probe this region's function.

• Dichotic listening, auditory processing tests
• Token Test (verbal comprehension), phonological discrimination
• Prosody recognition; biological motion (point-light) paradigms

Lesions and damage

Clinical findings expected with damage or dysfunction.

• Wernicke’s aphasia: fluent but meaningless speech (paraphasias, neologisms), impaired comprehension and repetition.
• Bilateral Heschl damage: cortical deafness or pure word deafness.
• Right: amusia, aprosodia.

In the model

How this structure is defined in the 3D model, and the data source.

Superior temporal and transverse temporal (Heschl) gyri.

References

Full citations for the card; links go to the paper (DOI) or a PubMed search.

1. Gervais H et al. Abnormal cortical voice processing in autism. Nat Neurosci 2004;7(8):801–802. DOI: 10.1038/nn1291