Lecture 5 – The Diencephalon: Integration, Homeostasis, Drives, and Motivation

These flashcards cover key terms and concepts related to the diencephalon, including its structure, function, and significant nuclei.

Diencephalon

The part of the brain located between the cerebrum and the brainstem, comprising the epithalamus, thalamus, hypothalamus, and ventral thalamus.

Epithalamus

A division of the diencephalon that includes the pineal organ, which modulates circadian rhythms.

Thalamus

A large, egg-shaped structure in the diencephalon that processes and relays sensory, motor, and emotional information to the cerebral cortex.

Pineal gland

A small, unpaired midline structure that produces melatonin and regulates circadian rhythms.

Melatonin

A hormone produced by the pineal gland that regulates sleep-wake cycles and is influenced by light exposure.

Hypothalamus

A small but crucial brain region that controls autonomic, endocrine, emotional, and somatic functions to maintain homeostasis.

Homeostasis

The body’s ability to maintain stable internal conditions despite external changes.

Suprachiasmatic nucleus (SCN)

The master circadian clock located in the hypothalamus that regulates biological rhythms based on light exposure.

Anterior pituitary

The front portion of the pituitary gland that secretes hormones such as growth hormone and thyroid-stimulating hormone, regulated by the hypothalamus.

Oxytocin

A hormone released by the hypothalamus that aids in childbirth and lactation, and is associated with bonding behaviors.

Vasopressin

Also known as antidiuretic hormone (ADH), it regulates water retention in the kidneys.

Mediodorsal nucleus

A major thalamic nucleus involved in emotional processing and motivation, projecting to the prefrontal cortex.

Lateral geniculate nucleus

A thalamic nucleus that relays visual information from the retina to the primary visual cortex.

Ventral posterior medial nucleus (VPM)

A thalamic nucleus that receives somatosensory input from the face.

Papez circuit

A neural circuit involved in the limbic system, connecting the hypothalamus with limbic cortical areas for emotional processing.

Mammillary bodies

Nuclei in the hypothalamus involved in memory and part of the Papez circuit.