source:
https://jamanetwork.com/journals/jamaneurology/fullarticle/795156An oddity that shows you what can happen when you don't have the full, updated manual
![Shocked :o](https://forum.drugs-and-users.org/Smileys/default/shocked.gif)
I'm sure that budding neurosurgeon stoners will find this of some help. Joke.
Pathological Crying Caused by High-Frequency Stimulation in the Region of the CaudalWiki Internal CapsulePathological crying has been rarely reported after deep brain stimulation. The exact neural substrate is unknown, but it is often assumed that pathological crying and the pseudobulbar syndromeWiki result from disturbances of a common neural pathway.Patient A 48-year-old woman with advanced Parkinson disease who received bilateral implantation of deep brain stimulators in her subthalamic nuclei.
Results Stimulation in the region of the caudal internal capsule resulted in pathological crying but no other features of pseudobulbar palsy.
ConclusionsAt least 1 of the pathways controlling crying passes through the region of the caudal internal capsule, and this pathway is distinct from those involved with laughter and nonemotional facial movements. Moreover, different stimulation frequencies may elicit either crying or anxiety but not both.
Pathological crying (PC) is a disorder of emotional expression characterized by involuntary, recurrent bouts of crying that are incongruent with the prevailing emotional, cognitive, and social context and is not associated with a sensation of sadness.
This condition may be accompanied by laughter (pathological laughter and crying [PLC]), which is assumed to share a common mechanism.
Pathological laughing and crying are often included as part of a wider pseudobulbar syndrome that may include disturbances of swallowing, speech,
bulbarWiki function, and exaggeration of facial, palatal, and jaw reflexes.
Although PLC is frequently encountered in a variety of neurological disorders, reports of crying or laughing following stimulation of the thalamus,
globus pallidus internaWiki,
subthalamic nucleusWiki (STN), and substantia nigra are rare and have all been associated with an emotional component.
Prior to this article, there has only been 1 other case of PC following deep brain stimulation (DBS) to our knowledge. In that article, PC, slurring of speech, and exaggeration of facial and gag reflexes were observed with monopolar stimulation through contacts extending from the subthalamus to the thalamus.
We report a case where high-frequency stimulation via a single contact in the region of the caudal internal capsule (CIC) resulted only in PC. This very localized effect argues for a distinct neural pathway for PC, separate from the larger constellation of symptoms that occur in PLC or the pseudobulbar syndrome.
The details of the case report can be found at the source link but here is an excerpt:
The patient did not know why she was crying and could not stop herself from crying. There was no sensation of sadness, pain, or persecution. Crying stopped within 5 seconds of stimulation cessation.The patient did not experience anxiety when she cried unless the episode was prolonged. She had no pseudobulbar symptoms during or immediately after episodes of stimulation-induced crying.
Our case confirms that PC can exist in the absence of other pseudobulbar symptoms, suggesting that separate neural pathways exist for the control of crying, laughing, and bulbar movements at least in the region of the CIC.
Further subdivision of this pathway may also be present because negative emotional responses (anxiety or crying) but not positive ones (laughing) could be produced by altering the stimulation frequency. Frequency-dependent neural modulation has been shown to be responsible for alterations in verbal fluency and motor symptoms due to the activation of different neural pathways in patients with STN-DBS.
Our case suggests that it may also affect the expression of different aspects of negative emotional responses.