| Term | Definition |
| Diencephalon | Thalamus
Hypothalamus
Epithalamus
Subthalamus |
| Epithalamus | Part of Diencephalon that regulates diurnal (sleep Cycle,body temperature, metabolic rate/digestion) and automatic body functions
Consists of the Pineal Gland & Habenular |
| Subthalamus | Part of Diencephalon that is Important in motor control |
| Hypothalamus | -Part of Diencephalon that mediates endocrine and metabolic states
-Is directly related to the limbic system
-Regulates body temp, water and food intake, metabolism, sexual behavior, anger, aggression. |
| Limbic System | takes care of our most primitive functions like sexual drive, hunger etc... |
| Main function of Thalamus | -acts as relay station receiving info & sending info to another part of the CNS |
| Other Functions of Thalamus | -Integrates sensorimotor information from the Basal Ganglia, Cerebellum, & Cortex
-Regulates function of association cortex & cortically mediated speech, language, & cognitive functions. |
| Three levels of Thalamic Nuclei | Medial
Ventral
Lateral |
| Anterior Nucleus of the Thalamus | Most primitive of thalamic nucleus
Relays info to the Limbic system,contributes to direction of:
digestive
respiratory
urogenital
endocrine functions |
| Reticular Nucleus | Thalamic nucleus that acts a sensory integrator and relayer of motor info
-Located between external medullary lamina and internal capsule |
| Intralaminar Nuclei | -Thalamic nucleus in core of internal medullary lamina
-Has afferent and efferent connections
-Modulates Excitability of association cortex |
| Intralaminar Nuclei Afferent Connections | -Brings info into the thalamus from various locations like the Globus Pallidus, Vestibular N, Superior colliculus, brainstem reticular formation, Cortex, Brainstem & Cerebellum |
| Intralaminar Nuclei Efferent Connections | Takes info away from the Thalamus to the
Basal Ganglia and Cortex |
| Dorsomedial Nucleus | Integrates emotion, thought, and judgment
Destruction lowers threshold for rage
May be related Korsakoff's syndrome |
| Dorsomedial Nucleus Afferent connections | Afferent(towards the thalamus) connections from prefrontal cortex, hippocampus, centromedianum nucleus, hypothalamus |
| Dorsomedial Nucleus Efferent connections | Efferent (away) projections to prefrontal and orbitofrontal cortex and limbic structures |
| Midline Nucelus Complex | -Medial Nucleus of the Thalamus
-Important in visceral functions
-Afferent Connections from brainstem reticular formation
-Efferent Connections to Cingulate gyrus and hypothalamus |
| Pulvinar | Lateral nuclear complex located on the posterior portion of the Thalamus
-Connects visual areas with association cortex
-Important in language formation, language processing, lexical properties, reading writing- |
| Ventral Anterior Nucleus | Thalamic Ventral Nuclear Complex
-Premotor cortex and skilled movements
-Voluntary movements |
| Ventrolateral Nucleus | Thalamic Ventral Nuclear Complex
-Contributes to voluntary motor tasks |
| Ventral Posterior Nucleus | Thalamic Ventral Nuclear Complex
Sensation from Body and Face |
| Lateral Geniculate Bodies | -located on the Thalamus (little posterior balls)
-Relay center for Vision
-Unilateral lesion would not cause vision lost, bilateral would |
| Medial Geniculate Body | -located on the Thalamus
-Relay center for Audition (cannot see on thalamus picture)
-unilateral destruction in this area you will still be able to hear in both ears b/c only 10% of info if ipsilateral. Bilateral lesion would result in hearing lost |
| Pineal Gland | Part of the epithalamus
-Important for hormone productions
-Inhibitory influence over gonadal function (sex function)
-Diurnal rhythms (Important for regulating sleep cycle) |
| Habenular Nucleus | Part of the epithalamus
-Serves autonomic function and emotional drives |
| Parts of the Subthalamus | 2 Parts:
-Subthalamic Nuclei
-Zona Incerta |
| Subthalamic Nuclei | - Controls Motor functions
- deterioration of this area causes Hemiballism (motor disorder: involuntary violent movements, persists only during wakefulness) |
| Zona Incerta | Visualmotor Coordinator |
| Parts of Hypothalamus | -Optic chiasm (where visiual info crosses over)
-Mammillary Bodies
-Hypophysis (Pituitary gland)
-Infundibular stem
-Tuber cinereum |
| Cognitive Functions of Thalamus | -Involved in language & speech functions
-Subcortical aphasia include a thalamic based aphasia (left dominant thalamus)
-Word Fluency Problems (decrease word output)
-Neurogenic stuttering from surgeries or stroke in thalamus |
| Thalamic Syndrome | -Gross detection of sensations at thalamic level
-Can result in very strong misinterpretations of sensation |
