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Disturbances of Ocular Movements and Blinking in Schizophrenia

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Disturbances of Ocular Movements and Blinking in Schizophrenia J Neurol Neurosurg Psychiatry: first published as 10.1136/jnnp.41.11.1024 on 1 November 1978. Downloaded from Journal ofNeurology, Neurosurgery, andPsychiatry, 1978, 41, 1024-1030 Disturbances of ocular movements and blinking in schizophrenia JANICE R. STEVENS From the Departments of Neurology and Psychiatry, University of Oregon Health Sciences Center, Portland, Oregon, USA S U M M A R Y Neurological examination and electroencephalograms and electro-oculograms, recorded by telemetry, from unmedicated patients with acute and chronic schizophrenia demonstrate a number of abnormalities of extraocular movement including staring, abnormai blink rate, absent glabellar reflex, and increase in horizontal eye movements. As potential clues to the pathophysiology of schizophrenia, these disturbances are analysed in relation to anatomical substrate and dopamine modulation of ocular movement, rapid eye movement sleep, and the neurological disorders in which similar disturbances of ocular movement occur. by guest. Protected copyright. In distinguishing dementia praecox from other consciousness; delusions, hallucinations, or formal forms of mental illness, Kraepelin (1913) called thought disorder; restricted affect; absence of signs attention to a number of ocular signs of the dis- and symptoms sufficient to make a diagnosis of order, including pupillary abnormalities, staring, affective illness or coarse brain disease. In ad- nystagmus, abnormal blinking, and blepharospasm. dition to the neurological examination, 36 of the Widespread use of neuroleptic medications has 55 medication-free patients and 12 normal control now induced a variety of neurological side effects subjects have had 2-24 hour electroencephalo- and sequelae which obscure the incidence of these grams (EEG) and electro-oculograms (EOG) signs and their relevance to the pathology of the recorded by radiotelemetry during which spontane- schizophrenias. Because these ocular signs may ous behaviour was recorded continuously by a provide clues to the pathology of the schizophrenia trained observer. Bipolar EEGs were recorded syndrome, it seemed worth while to document from tin or gold disc electrodes attached to the them carefully in medication-free patients. scalp with collodion at central-parietal (C3-P3; C4-P4) and temporal (T3-T5; T4-T6) positions Subjects and methods bilaterally. Lateral eye movement was recorded between electrodes placed at the outer canthus of Complete neurological examinations have been each eye. Vertical movements and blinks were performed on 45 patients who were free from recorded between electrodes placed immediately medication for periods of one month to four years, above and below one eye. Subjects wore a small and 10 patients who had never received drugs or multiplexed 8-channel transmitter (weight 90 g, http://jnnp.bmj.com/ other physical treatment. Nine patients were seen Benton Instrument Company) held firmly to the within a year of diagnosis, 14 had been diagnosed head by a special cap. between one and five years, and the remaining 29 During the recording period, patients were in patients, longer than five years. The youngest their rooms or the dayroom within a radius of 40- patient was 17 years of age, the oldest, 49 years. 50 yards of the receiver antenna. They slept in their Thirty-one were men, 24 were women. own beds, and carried on their usual hospital The diagnosis was made by senior staff con- routine. Electroencephalographic and EOG signals sensus and required the following five of the seven were recorded on a 7-channel FM tape recorder on September 30, 2021 criteria stipulated by Taylor and Abrams (1975): monitored by an ink-writing polygraph. Receiving illness duration greater than six monrths; clear and recording devices were centrally placed in a hallway near the ward dayroom. The polygraph Supported by National Institutes of Health Grant 18055. run at a of 15 mm second and Address for reprint requests: Department of Psychiatry, University of was speed per Oregon Health Sciences Center, Portland, Oregon 97201, USA. could be correlated continuously with ongoing Accepted 23 June 1978 behaviour and accelerated to 30 mm per second for )24 J Neurol Neurosurg Psychiatry: first published as 10.1136/jnnp.41.11.1024 on 1 November 1978. Downloaded from Disturbances of ocular inovemenits and blinking in schizophrenia 1025 more detailed examination during periods of A 17 year old boy avoided eye contact because unusual behaviour. Frequency modulated tape was "I'm afraid you'll read my thoughts." EEG accompanied recorded at 17 inches per second, and portions of No change in simultaneous these clinical events. the taped record were played back during be- havioural events of particular interest and for ALTERED BLINK RATE subsequent analysis. Behavioural observations Although both Kraepelin (1913) and Bleuler (1950) were recorded by a trained observer on a written remarked upon increased blinking in dementia log and were coded by number at the moment of praecox, quantitative studies of blinking in this occurrence on a time code placed on one channel illness are lacking. Abnormalities of blinking in of the tape recorder and polygraph, assuring exact this group of unmedicated schizophrenic patients correlation between EEG-EOG recording and fell into three categories: (1) decreased blinking, behavioural events. staring, and absent eye contact, most commonly seen in acute exacerbations of the disorder; (2) Results steady increase in blinking at rest in patients with chronic schizophrenia; (3) episodic paroxysms of Neurological examination of this group of patients rapid rhythmical blinking associated with demonstrated that, apart from the characteristic hallucinations, sudden impulsive acts, or deluded abnormalities of mental state and skeletal motor speech. activity (stereotyped behaviours, rocking, bizarre Sixteen patients demonstrated episodes of postures), the most common signs were dis- rhythmic or paroxysmal blinking at rates up to turbances of ocular contact and movement. These 2.5-3 per second, and seven patients, four of whom by guest. Protected copyright. included staring, abnormal blinking, saccades, and had never received neuroleptic treatment, dis- ocular pursuit. Prolonged telemetered EEG-EOG played absent or decreased blinking (0-1 per confirmed the clinical evidence of abnormal ocular minute). movements. Although slow or sharp activity ap- Eight patients showed abrupt change in blink peared over the left or right temporal region of rate during delusional excitement, while speaking one-third of these patients, these abnormalities in response to hallucinated voices, or during could not be associated with the clinical changes autistic reveries. nor with the appearance of abnormal ocular A 26 year old former college student, in hospital activity. In contrast, the oculomotor changes were for nine years with an unrelenting dementia frequently correlated with abnormalities of praecox, sat indolently in the dayroom of the perception and attention. hospital blinking steadily two and a half times per second. He reported that he was in a "waking ABNORMALITIES OF EYE CONTACT nightmare" of frightening sexual experiences A fixed penetrating stare directed into the (Fig. 1). A patient with acute catatonia who was studied examiner's eyes, at a distant point, or avoidance before all treatment blinked only two to three and failure of eye contact were noted in 34 times per minute during the day, but exhibited patients. These signs were equally common in 2-10 second epochs of rhythmic blinking two and acutely and chronically ill individuals, and usually a half to three times per second associated with a responded promptly to neuroleptic treatment in posture of supplication or deep sighing respiration patients with acute psychosis. Interrogation of the at intervals during a sleepless night (Fig. 2). patient rarely provided a clear explanation for http://jnnp.bmj.com/ staring or diversion of gaze. A few individuals ABNORMAL BLINK (GLABELLAR) REFLEX indicated that staring or avoidance of eye contact In response to gentle taps of the glabella repeated was a response to perceptual change as indicated at one second intervals, most normal adults by the following examples: respond by single blinks to the first two to five taps, A 21 year old man with chronic paranoid schizo- then stop blinking unless stimulation is discon- phrenia, who stared fixedly at the examiner, tinued for 10-20 seconds, after which the response explained "your face is turning into an animal." returns and again habituates after repetition The mother of a 20 year old schizophrenic girl (Overend, 1896). Twelve of the 50 patients in this on September 30, 2021 reported: "when I go to the hairdresser I tell her study had no response to glabellar tap, six failed I'll be right back. When I come back an hour to habituate the reflex after 10 or more taps, and later and walk in she just stares at me like I'm a new person to her. At other times she stares at 14 patients displayed paroxysmal bursts of rapid her father like a stranger and shouts 'Get him out blinking to each tap on repetition. Absent blink of here, he's doing things to me. Who is he? Get reflex was most common in patients with acute him out!'" exacerbation of psychosis, while persistent or J Neurol Neurosurg Psychiatry: first published as 10.1136/jnnp.41.11.1024 on 1 November 1978. Downloaded from 1026 Janice R. Stevens A.D. 26 YEAR OLD 0' CHRONIC UNDIFFERENTIATED SCHIZOPHRENIA 4/26/76 No Med Mo C3- P3 -v---'-, , ,AIH&.6AA- T3-T5 -I-.- C4-P *.,- s>---5s> -'> 9\¢;-x--\->-\w<>-\V-\'->h>o >M N 5 5 S T > t + T4 -T6^i N \ eye t l>8\l2S>%,\\%, s,l n\ 1 P ,1X,;,i,tAllili5 #,blill .A.MM.M,i---- - . Lot eye, VMAeAyAAI A* r- 2-., I v -1W.-i - . 3:00 pm Sitting Quietly, Blinking 4/26 3:14 pm "I keep feeling Im going to bed with a womon. 50 jV 5/7/76 No Meds 6 Wks by guest. Protected copyright. *.w ., _ ..... .JAe,,.-.%k,, As j 2' 1. 4:02 pm Dozing No clinical sign 6 43 pm Eyes closed "My problem is think I'm not born.
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