THE NEUROLOGIST WHO COULD NOT STOP RHYMING AND RAPPING

Abstract

This report describes a neurologist who, at age 55, developed an irrepressible urge to rhyme after a series of strokes and seizures. His strokes included a right posterior cerebellar infarction and a right thalamic lacune. His subsequent seizures were focal-onset with and without impaired awareness or secondary generalization, which emanated from the left frontotemporal region. On recovery and control of his seizures, he described the emergence of an irresistible urge to rhyme, even in thought and daily speech. His focus on rhyming first manifest as a new affinity for poetry and grew and mutated to a focus on rap music. By age 63 his interest in rap had led him to participate in freestyle rap at an inner-city center for rap improvisation and performance. The potential source for his acquired rhyming and rapping are discussed in terms of his unique insights as a neurologist and the current literature on the brain and rhyme. This patient’s rhyming and rapping may have been initially facilitated by epileptiform activation of word sound associations in the left frontotemporal language areas and possibly perpetuated interictally as a compensation for impaired cerebellar effects on timed anticipation.

INTRODUCTION

The origin of rhyming, poetry, and word sound associations in the brain is incompletely understood. Studies in normals with functional magnetic imaging (fMRI), event related potentials (ERPs), and other neurological tests have suggested that word sound associations are mediated by the left hemisphere inferior frontal cortex (IFC) and temporal regions involved in language (Kareken et al., 2000; Khateb et al., 2007; MacSweeney et al., 2009; Poldrack et al., 2001), but other studies emphasize the importance of related creativity, intonation, and prosody from the right hemisphere (Durfee et al., 2021; Zeman, 2013). Rhythmic ability also participates in rhyming activities such as poetry, rapping, and musical lyrics. The analysis of patients who experience the emergence of rhyming behavior due to neurological disease can further clarify the origin of rhyming in the brain.

One such, unique patient is a neurologist who developed a focus on rhyme and became a rapper after sustaining strokes and experiencing seizures. He became well-known for traveling to a cultural center of freestyle or improvised rap and actively participating and performing on stage. The artform of rap is a particularly good example of word sound associations. In freestyle rap, the artist must improvise lyrics that rhyme while synchronized to the musical beat. This requires rapid online selection and phonetic encoding of words that rhyme and their articulation in verse or rhythm. As a neurologist, this patient was able to provide unique insights into his acquired rhyming and rapping behavior. A further review of his medical and imaging records, and interviews with his widow, daughter, and a lifelong friend, indicated a number of possible mechanisms for the emergence of rhyming behavior in this patient.

CASE

A right-handed neurologist with a history of hypertension began having unexplained blackout spells at about age 53. Two years later, he presented with a generalized tonic-clonic (GTC) seizure. Extensive review of his neurological examination indicated developmental stuttering and mild left-sided dysmetria, which resolved. MRI disclosed prior strokes involving the right posterior cerebellum in the posterior inferior cerebellar artery (PICA) distribution, a right thalamic lacune, and scattered periventricular white matter hyperintensities. The stroke work-up did not disclose major arterial disease or a cardioembolic source, but he had laboratory findings consistent with the antiphospholipid syndrome. In addition to phenytoin, he was started on aspirin (81 mg), which was later switched to coumadin as an outpatient. The patient remained free of any GTC seizures. A progress note and an early letter describing the patient indicated a possible right temporal source for his seizures (Mendez, 2005); however, subsequent reviews of his electroencephalographs (EEG) failed to verify this localization.

The patient and his wife reported that his personality changed after his GTC seizure. He developed a new interest in writing poetry, something he never previously cared for, along with an increased ability to rhyme. The patient felt that his rhyming behavior began after a stroke and that “a posterior area of the left cerebral hemisphere that controls rhythm and beat has become stronger since the stroke”. He described words as “continuously rhyming in his head” and expressed the need to write them down and show his writings to others. He also explained that, whenever he rhymed, his tendency to stutter disappeared, and his speech “flowed”. As time went by, he also developed an intense interest in Buddhist chants. Eventually, his wife and friend reported that he could not stop speaking in rhyme and would finish all of his sentences with rhyme or simple rhyme couplets, e.g. “Hello Norene, you look pristine”.

At age 64, he was rehospitalized with new-onset mild left-sided weakness, a left pronator drift, and a tendency to veer to the left on gait. MRI showed a recent white matter infarction about 1.2 cm in diameter in the right centrum semiovale. During hospitalization, he was observed to have a focal seizure where he “lost awareness” with a “blank stare”. The patient admitted to having 1–3 “auras” per month characterized as brief feelings of being “unwell inside”, which could be followed by a sensation “rising” in his stomach and a brief alteration of awareness. At other times, his auras led to brief “right upper extremity jerking”. His phenytoin level was low and his dosage was readjusted prior to discharge.

The patient was hospitalized once more at age 68, this time for confusion, agitation, aggression, and an increased frequency of his focal-onset seizures. He appeared to be in an encephalopathic state from ongoing or subclinical seizures. On admission, he was disoriented, confused, and had poor attention (e.g, digit span of four forward). Although his language was fluent, he was unable to perform normally on delayed recall, visuospatial constructions, and frontal-executive tasks. The rest of his neurological examination did not show new abnormalities, and his MRI scan only showed the old right PICA distribution and thalamic strokes and white matter hyperintensities (See Figure 1). His EEGs, however, revealed ongoing epileptiform activity phase reversed at F3 and F7-T3 with spread to bursts of diffuse bilateral 3–5 Hz sharp waves running for 3 seconds. There were also random and intermittent 4–5 Hz or 1–2 Hz polymorphic slow waves maximum in that left anterior temporal region suggesting an old resolved lesion. The patient’s clinical and EEG seizure activity was suppressed with several anti-epileptic agents but eventually controlled on valproic acid (VPA), with concomitant resolution of his agitation and confusion.

FIGURE 1: Magnetic Resonance Imaging (MR) of the Brain.

MRI scan obtained during the patient’s hospitalization for encephalopathy at age 68. The top two images are fluid-attenuated inversion recovery scans, in the axial plane, showing a right posterior-inferior cerebellar hemisphere stroke, a right white matter infarction, and evidence of scattered white matter hyperintensities, some located in the left inferior frontal region. The bottom two images are T2 scans, also in the axial plane, more clearly showing the right cerebellar stroke and the right thalamic stroke.

He underwent further assessment as he cleared from his encephalopathic state. On recovery, he continuously responded in rhyme during conversation, e.g., “Since VPA, I’m not in a battle like a bunch of cattle”, and, when discussing taking all of his medications at one time, “l’d take it all at once, I’d be a dunce, because my stomach would get upset; that’s a sure bet.” He described potentially working with his doctors as working with “the peaches and cream, that’s my dream”. Neuropsychological testing concluded that he had vascular cognitive impairment with significant residual deficits in verbal and nonverbal memory and executive functions (See Table 1). Although his vocabulary score was high average, he showed deficits in confrontational naming, phonemic fluency, and semantic fluency in relation to his educational background. A fluorodeoxy-glucose (FDG) PET scan reported focal hypometabolism in the right lateral cerebellum consistent with his PICA stroke, and relatively increased metabolism in the striatum, visual cortex, and primary motor sensory areas (See Figure 2).

TABLE 1:

NEUROPSYCHOLOGICAL TESTING

Raw Score or T-Score (bolded)		%ile
Mini-Mental Status Exam (Errors calculations, recall)	25/30
Wechsler Abbreviated Scale of Intelligence (WASI)
Full Scale Intelligence Quotient (IQ)	99	47th
Vocabulary	59	82nd
Similarities	55	69th
Verbal IQ	110	75th
Block Design	31	3rd
Matrix Reasoning	51	54th
Performance IQ	86	18th
Attention and Concentration
Trailmaking A (seconds; 0 errors)	80”	<1st
Trailmaking B (seconds; 0 errors)	112”	8th
Wechsler Adult Intelligence Scale (WAIS)-III Digit Span	9	37th
Forward, Backward	7, 5
WAIS-III Letter - Number Sequencing	7	25th
Language Functioning (no paraphasic errors)
WASI Vocabulary	59	82nd
Boston Naming test with Stimulus Cues	46/60	<1st
Boston Naming Test with Phonemic Cues	54/60
“F-A-S” Verbal Fluency (F (10) + A (4) + S (7))	21	4th
Animal Naming/minute	10	3rd
Visuospatial Functioning
WASI Block Design	31	3rd
WASI Matrix Reasoning	51	54th
Hopkins Verbal Learning Test
Trial 1 (3) + Trial 2 (4) + Trial 3 (4)	11/36	<1st
Delayed Recall	0/12	<1st
True Positives; False Positives	8; 6
Brief Visuospatial Memory Test-Revised
Trials 1, 2, 3	0, 2, 1	1st, 2nd, <1st
Total Recall	2	<1st
Delayed Recall	1	<1st
Recognition Hits, False Alarms	3, 4	3–5th, <1st
Executive Functioning
Trailmaking B (seconds; 0 errors)	112”	8th
Stroop Color (seconds; 1 error, 0 near-misses)	150”	<1st
Stroop Word (seconds; 0 errors, 0 near-misses)	79”	<1st
Stroop Interference (seconds; 4 errors, 1 near-miss)	288”	<1st
“F-A-S” Verbal Fluency (5 perseverations)	21	4th
Animal Naming (0 perseverations)	10	3rd
WASI Similarities	55	69th
WAIS-III Letter-Number Sequencing	7	25th
Grooved Pegboard Test
Dominant (R) (0 errors)	211”	<1st
Nondominant (L) (0 errors)	325”	<1st
Trails A (Time in Seconds)	80”	<1st

FIGURE 2: Fluorodeoxy-Positron Emission Tomography (FDG-PET) of the Brain.

FDG-PET scan obtained after recovery from his encephalopathy at age 68. The images are in a the axial plane. The first more ventral scan shows a region of hypometabolism in the right posterior inferior cerebellar hemisphere. The second more dorsal scan shows a right thalamic region of hypometabolism and relatively increased metabolic activity in the striatum.

During this assessment, the patient and his wife revealed that he had been participating in freestyle rap for the prior five years. The patient stated that he needed to rap whenever he was feeling “high” and because he was always thinking and speaking in rhyme. He considered that rapping might help control his seizures, and his wife added that her husband’s participation in rap made him very happy. His interest in rap had increased so that by about age 63 he was driving, taking the bus, or even walking from his affluent community to an inner-city cultural center for open-microphone workshops of freestyle rap where he participated as “Dr. Rapp”, later “Dr. Flow”. The patient stood out as an older Caucasian physician among a predominantly young and African-American crowd. He was able to perform to a level that he was mostly accepted and not forced off stage. Moreover, the patient, who was of the Jewish faith, began putting Holocaust related themes to rap within the context of melodic compositions by Chopin and Mozart. He reported suddenly doing the Holocaust in rhyme while providing visitors a guided tour at a Holocaust remembrance center. He shared many of his poems and rhymes, freely giving them to the medical staff and others (See Table 2). The patient had planned to write a book on his experiences, particularly promoting the healing power of rap and its effects on neuroplasticity. Unfortunately, he died from cancer at age 76.

Table 2:

Rhyme and Rap

A. About Rap Lyrics: “ln life we have alot of strife and we’ve got to be in rhyme all the time. We’ve got to be movin’ and groovin’ and everything will be in proper rhyme all the time.” “lf you wish I can rhyme all the time. Everything was good like it should be in the’hood.”

B. Holocaust “God, this is a tough thing to write The feeling I got in my heart tonight Just to think of the Holocaust So deep and sadly blue And still so many people Don’t think it’s true.”

C. To doctors and nursing staff: All standing tall Thank you so much for your care ln the long run, everything was fair At times I was completely out of rhyme Nothing was fine I was rough, Tough And had enough But believe me With no fee Thank you so much To my life With strife You added such a special touch So please take care And everything in life Will be fair --Dr. Flow M.D. Extraordinary

D. To doctor working with dementia: ... who thinks of dementia all the time and he thinks it’s fine.. but for people who are dement and heads full of cement.. I can get them better right to the letter all the way from Hudson’s Bay to L.A. and to the South Bay.. ...Just trying to express my feelings with alot of dealings. Am I right or am I wrong like the Viet Cong? ...And that’s why the Neurologists they don’t want to reason and think it’s treason It’s very simple like a pimple. ...I can get happy and flappy without med because it’s read by the Fed. A feel is the deal. ...That’s the score and I can go right back to the core; This is the deal... the score last week was 4 to 4 for Baltimore; And I had to take a peek. …I sure know the cure that by rhyme all the time This will help people with Autism, language disorders, mental retardation and People who are depressed-- feel less like they’re a pest Some rap when depressed so they Don’t feel less; ...And there’s glory to their story.”

DISCUSSION

This patient illustrates the emergence of a compulsion to rhyme after seizure control and strokes. His rhyming behavior is consistent with a prior report of left temporal origin seizure control triggering residual rhyming behavior (Woollacott et al., 2015). The mechanism for a fixation on the sound of words from neurological disease is unclear, but it may reflect a release, facilitation, or stimulation of the left IFC and left temporal areas involved in language and in rhyme judgments. In this patient, the presence of a stroke involving the right posterior cerebellar hemisphere, per his report, may also indicate the continued use of rhyme as compensation for impaired cerebellar functions in the timing of speech and language.

An initial consideration is the development of rhyming behaviors as obsessive-compulsive symptoms (OCS). OCS are common among persons with epilepsy, especially those with severe focal-onset seizures of temporal lobe origin (Ertekin et al., 2009; Isaacs et al., 2004; Kim et al., 2020; Monaco et al., 2005), and may emerge or disappear after epileptic surgery (Guarnieri et al., 2005; Roth et al., 2009). This patient did not have any new onset OCS that were not related to rhyming or rapping, nor was his rhyming directly correlated with epileptiform activity. Nevertheless, his symptoms do suggest that left frontotemporal epileptiform discharges initiated his fixation on word sounds associations.

There are several types of word sound associations that may manifest as a result of brain disease. ln addition to rhyming, with correspondence in terminal word sounds, and the related alliteration, with correspondence in initial word sounds, there may be clanging, or the sequential repetition of words with similar sounds, and punning, or the humorous use of words based on their sound (Otake & Cutler, 2013). Clanging and punning, which are associated with mania or schizophrenia (Andreasen, 1986), can emerge from acquired brain disease, such as right temporal predominant frontotemporal dementia (FTD) with relative sparing of left hemisphere frontal language areas (Granadillo & Mendez, 2016; Mendez et al., 2017). Similar “compulsive versifying” with a residual tendency to word sound associations has occurred after lamotrigine treatment of focal seizures of left temporal origin (Woollacott et al., 2015). Others have reported new-onset poetry writing and “speaking in rhyme” in association with subarachnoid hemorrhage with left hemispatial neglect (Lythgoe et al., 2005).

As in this patient, active rhyming requires left hemisphere language areas, particularly the left IFC. In fMRI studies, rhyme judgment tasks involve the left IFC, which is engaged in phonological tasks, as well as the left inferior posterior temporal or fusiform gyrus and adjacent areas (Kareken et al., 2000; Poldrack et al., 2001). Subvocal word rhyming activates the left IFC Broca’s area (Brodmann’s area [BA] 44), left dorsolateral prefrontal cortex (DLPFC; BA 9–46, BA 8–9), left middle temporal gyrus (BA 22), and left fusiform gyrus (BA 37) (Kareken et al., 2000). On a rhyme judgment task, dyslexics and deaf individuals have greater activation than a hearing non-dyslexic group across a large portion of the left IFC, including the pars triangularis and the pars opercularis (MacSweeney et al., 2009), and ERP analysis during a rhyming task predominantly engages the left frontal and temporal areas (Khateb et al., 2007). Another fMRl study, a correlation analysis of “creative writing” minus “copying”, indicates that creative word choice activates not only the left IFC (BA 45), but also the left temporal pole (BA 38) involved in verbal and semantic memory (Shah et al., 2013). In addition, an fMRI study of rap music finds that improvised rap performance, in contrast to previously memorized lyrics, results in increased left medial prefrontal activation with relative deactivation of the right DLPFC (Liu et al., 2012). From these studies, it appears that this patient must have “activated” an intact network of left frontotemporal brain regions that are critically necessary for improvising rhyme and rap (Beaty, 2015).

Reports of patients with neurological disease show a dissociation between the abilities for rhyme and rhythm, which are involved in verse, poetry, and rap music. There is lateralization of fine temporal processing of verbal and auditory sounds in the left auditory areas or Heschl’s gyrus (Breitling et al., 1987). Left hemisphere lesions can cause a “rhythm agnosia” with abnormal recognition of simple rhythm patterns (Assal & Buttet, Agraphie et conservation de l’ecriture musicale chez un professeur de piano bilingue./1983; Mavlov, 1980), whereas, right temporal lesions can cause auditory agnosia with enhancement of rhythm appreciation and abnormal melodic sequencing but with preserved rhythm (Griffiths et al., 1997; Mendez, 2001; Peretz et al., 1994). Moreover, the appreciation of beat or meter has been selectively preserved after resection of right temporal tumor (Baird et al., 2014), and, in behavioral variant FTD (bvFTD), right frontotemporal hypofunction could lead to enhanced rhythm appreciation and the “release” of rhyming abilities (Mendez, 2001). In contrast, the right hemisphere has a role in rhythmic aspects when there is emotion in poetry as well as music (Durfee et al., 2021; Zeman, 2013). A paradoxical functional facilitation of artistic talent among FTD patients and others with brain dysfunction also appears to result from hypoexcitability involving the left frontotemporal area (Miller et al., 1998). Together, these findings point to rhythmic aspects of rhyme and rap in the left temporal region and emotional and creative aspects of poetry and rap in right frontotemporal areas, both of which were relatively functionally spared in this patient.

This patient may have had disturbed rhythm and timing from a different source, his right posterior cerebellar stroke (Jacobi et al., 2021; Schmahmann & Sherman, 1998). There are crossed cerebellar-cerebral-cerebellar connections, and cerebellar lesions in the posterior lobes lead to executive deficits due to alterations in cognitive timing and sequencing (Argyropoulos et al., 2020; Hoche et al., 2018; Marien et al., 2014; Schmahmann & Sherman, 1998). Crossed right cerebellar-left cerebral connections participate in language processing, such as phonological grouping and sequencing (M. Leggio & Molinari, 2015; M. G. Leggio et al., 2000; Marien et al., 2014; Marien & Borgatti, 2018), and fMRl data during rhyme judgment reveals reciprocal interactions between right cerebellar lobules Vl and Crus l, and the left IFC and left lateral temporal cortex (Booth et al., 2007; Marien et al., 2014). In essence, the cerebellum optimizes cognition and language by proactively modulating excitability for maximal attention-perception sensitivity based on expectations of time of arrival of critical information (Breska & Ivry, 2021; Hickok et al., 2015; Jacobi et al., 2021; Lakatos et al., 2013; Schmahmann et al., 2007). Studies show that disturbance in this function can promote stuttering or impede fluency among stutterers (Brown et al., 2005; Fox et al., 2000; Yang et al., 2016); a dysfunction potentially overcome in this patient by reliance on word sound associations for timing.

The combined literature suggests a model, albeit tentative and speculative, for this patient’s rhyming and rapping behavior. First, his left frontotemporal epileptiform discharges may have “activated” left frontotemporal language regions involved in rhyming. Although the patient felt that a stroke initiated his focus on rhyme and rapping, the medical records document the behavior at age 55 after starting an antiseizure medication, similar to a prior patient reported in the literature (Woollacott et al., 2015). His early blackouts from age 53 were probably post-stroke focal seizures which secondarily generalized at age 55. Second, the further maintenance of his focus on word sound associations may have compensated for lack of timing anticipation from his PICA stroke. His description of overcoming a tendency to stutter is a potential clue to a role of cerebellar dysmetria for speech and language in his disorder (Schmahmann, 1998).

In conclusion, this report describes a very unique neurological patient who developed an irrepressible urge to rhyme after a series of strokes and seizures. Based on the available retrospective clinical information and more recent interviews with those who knew him, his strokes and seizure management resulted in the constant thinking and speaking in rhyme, a new-found affinity for poetry, and a late-life participation as a rapper. Although he was not able to be studied in more detail, future studies and reports can evaluate the proposed model for this patient and the source of new-onset rhyming behavior from the brain.