circle of Willis

a ring of blood vessels on the underside of the brain, formed by links between branches of several major arteries—the basilar artery, internal carotid artery, anterior cerebral artery, anterior communicating artery, middle cerebral artery, posterior cerebral artery, and posterior communicating artery. By providing multiple pathways for blood circulation, this arrangement ensures the continuous flow of oxygenated blood to the brain in the event a supplying artery becomes blocked or constricted as a result of an injury, disease, or other condition. Also called arterial circle. [Thomas Willis (1621–1675), English anatomist and physician who was the first to illustrate this area definitively and provide a description of its function]

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Psychology term of the day

March 17th 2025

enactment

1. the acting out of an important life event rather than expressing it in words. See psychodrama.

2. in some forms of psychoanalytic psychotherapy, the patient’s reliving of past relationships in the transference relationship with the therapist and, conversely, the therapist’s move away from active neutrality to unwittingly intertwine personal issues into symbolic interactions with the patient (a countertransference phenomenon). Attunement to the relational patterns that emerge in this therapeutic relationship offers the therapist an opportunity to help the patient acknowledge and work through similar patterns in the patient’s relationships with others. See also relational psychoanalysis; self psychology.

3. in some forms of couples therapy, a technique in which the therapist recreates areas of conflict between partners in order to facilitate bonding moments.

4. see structural family therapy.