Posterior Cingulate & Precuneus

Anatomy

• Posterior cingulate cortex (BA 23, 31), retrosplenial cortex (BA 29–30), precuneus (medial BA 7).
• Around and above the splenium of the corpus callosum; the parieto-occipital sulcus lies posteriorly.
• One of the most metabolically active and most highly connected regions of the brain.
• Blood supply: ACA (pericallosal), PCA (parieto-occipital branches).

Functions

• Hub of the default mode network (DMN): highest activity at rest, inward-directed thought.
• Retrieval of autobiographical memory, self-related processing.
• Imagining the future (episodic simulation), mind-wandering.
• Retrosplenial: spatial navigation, transforming between viewpoints.
• Precuneus: visual imagery, episodic memory, awareness.

Connections and chemistry

• mPFC (anterior hub of the DMN)
• Hippocampus and parahippocampal cortex
• Angular gyrus
• Thalamus — anterior nucleus
• Cingulum bundle

Development

Developmental course through childhood and adolescence.

• The DMN is fragmented in infancy; long-range connections strengthen in childhood and adolescence (Fair et al., 2008).
• The anticorrelation between the DMN and task-positive networks becomes clearer with age.

Clinical

• ADHD: insufficient suppression of the default mode network (DMN) during tasks, and attentional lapses (Sonuga-Barke and Castellanos, 2007). In youth with ADHD whose DMN suppression was weak off medication, a stimulant brought suppression to healthy levels and normalized the influence of the ventral ACC on lateral PFC (Peterson et al., 2009; 16 patients). B
• ASD: differences in DMN connectivity.
• Depression: increased DMN activity linked to rumination.
• Trauma: dissociation and changes in self-perception.

Treatment

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

• Stimulants normalize DMN suppression during tasks; regulating the network linked to “mind-wandering” may be one mechanism of action (Peterson et al., 2009). B
• In depression, rumination-focused CBT and behavioral activation target the DMN’s excessive inward focus; related network findings are on the mPFC card (Kaiser et al., 2015). B
• In trauma and dissociation, trauma-focused CBT (TF-CBT) is first line in children and adolescents. A

Assessment

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

• Resting-state fMRI (DMN connectivity)
• Autobiographical memory interview
• Virtual navigation and imagery tasks

Lesions and damage

Clinical findings expected with damage or dysfunction.

• Topographic disorientation (retrosplenial — getting lost).
• Episodic memory impairment, changes in awareness.

In the model

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

Posterior cingulate, isthmus cingulate and precuneus.

References

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

1. Peterson BS et al. An fMRI study of the effects of psychostimulants on default-mode processing during Stroop task performance in youths with ADHD. Am J Psychiatry 2009;166(11):1286–1294. Search PubMed