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The resolution of the Latah paradox

Simons RC

J. Nerv. Ment. Dis., 1980 Apr;168(4):195-206.
PMID: 7365478

Latah is a culture-bound syndrome from Malaysia and Indonesia. Persons exhibiting the Latah syndrome respond to minimal stimuli with exaggerated startles, often exclaimning normally inhibited sexually denotative words. Sometimes Latahs after being startled obey the commands or imitate the actions of persons about them. Most episodes of Latah are intentionally provoked for the amusement of onlookers. Similar sets of interactive behaviors have been reported from genetically and culturally unrelated populations (e.g., Bantu, Ainu, and French Canadians). Since competent anthropological investigators have shown Latah to be intimately tied to specific factors in the cultural systems of the Southeast Asian societies in which it is found, its occurrence elswhere has been considered paradoxical. New data, including films and videotapes of hyperstartling persons from Malaysia, the Philippines, Japan, and the United States, suggest a model capable of resolving the apparent paradox by showing how the various forms of latah are culture-specific exploitations of a neurophysiological potential shared by humans and other mammals. Latah provides an especially revealing example of the complex ways in which neurophysiological, experiential, and cultural variables interact to produce a strongly marked and phenomenon.

Matched MeSH terms: Reflex, Startle*
The idiom of latah: reply to Dr. Simons

Bartholomew RE

J. Nerv. Ment. Dis., 1995 Mar;183(3):184-6.
PMID: 7891068
Matched MeSH terms: Reflex, Startle
Latah: an Indonesian startle syndrome

Bakker MJ, van Dijk JG, Pramono A, Sutarni S, Tijssen MA

Mov Disord, 2013 Mar;28(3):370-9.
PMID: 23283702 DOI: 10.1002/mds.25280

The nature of culture-specific startles syndromes such as "Latah" in Indonesia and Malaysia is ill understood. Hypotheses concerning their origin include sociocultural behavior, psychiatric disorders, and neurological syndromes. The various disorders show striking similarities despite occurring in diverse cultural settings and genetically distant populations. They are characterized clinically by exaggerated startle responses and involuntary vocalizations, echolalia, and echopraxia. Quantifying startle reflexes may help define Latah within the 3 groups of startle syndromes: (1) hyperekplexia, (2) startle-induced disorders, and (3) neuropsychiatric startle syndromes. Twelve female Latah patients (mean age, 44.6 years; SD, 7.7 years) and 12 age-, sex- and socioeconomically matched controls (mean age, 42.3 year; SD, 8.0) were studied using structured history taking and neurological examination including provocation of vocalizations, echolalia, and echopraxia. We quantified auditory startle reflexes with electromyographic activity of 6 left-sided muscles following 104-dB tones. We defined 2 phases for the startle response: a short latency motor startle reflex initiated in the lower brain stem <100/120 ms) and a later, second phase more influenced by psychological factors (the "orienting reflex," 100/120-1000 ms after the stimulus). Early as well as late motor startle responses were significantly increased in patients compared with controls (P ≤ .05). Following their startle response, Latah patients showed stereotyped responses including vocalizations and echo phenomena. Startle responses were increased, but clinically these proved insignificant compared with the stereotyped behavioral responses following the startle response. This study supports the classification of Latah as a "neuropsychiatric startle syndrome."

Matched MeSH terms: Reflex, Startle/physiology*
A clinical and survey study of latah in Sarawak, Malaysia

Chiu TL, Tong JE, Schmidt KE

Psychol Med, 1972 May;2(2):155-65.
PMID: 5034110 DOI: 10.1017/S0033291700040629

During a psychiatric survey in Sarawak, subjects demonstrating latah were examined separately, both clinically and with a questionnaire. Latah occurred only in females, mainly Malays, occasionally Ibans, and never Chinese. Fifty latah subjects were examined, seven were firmly diagnosed as being mentally ill, and another 13 demonstrated mild psychiatric disorders. Dream content indicated an overt sexual component

Matched MeSH terms: Reflex, Startle*
Fulltext Behavioural effects of APH199, a selective dopamine D4 receptor agonist, in animal models

Chestnykh D, Graßl F, Pfeifer C, Dülk J, Ebner C, Walters M, et al.

Psychopharmacology (Berl), 2023 Apr;240(4):1011-1031.
PMID: 36854793 DOI: 10.1007/s00213-023-06347-1

RATIONALE: The dopamine D4 receptors (DRD4) play a key role in numerous brain functions and are involved in the pathogenesis of various psychiatric disorders. DRD4 ligands have been shown to moderate anxiety, reward and depression-like behaviours, and cognitive impairments. Despite a series of promising but ambiguous findings, the therapeutic advantages of DRD4 stimulation remain elusive.
OBJECTIVES: The investigation focused on the behavioural effects of the recently developed DRD4 agonist, APH199, to evaluate its impact on anxiety, anhedonia, behavioural despair, establishment and retrieval of alcohol reinforcement, and amphetamine (AMPH)-induced symptoms.
METHODS: Male C57BL/6 J mice and Sprague-Dawley rats were examined in five independent experiments. We assessed APH199 (0.1-5 mg/kg, i.p.) effects on a broad range of behavioural parameters in the open field (OF) test, conditioned place preference test (CPP), elevated plus maze (EPM), light-dark box (LDB), novelty suppressed feeding (NSF), forced swim test (FST), sucrose preference test (SPT), AMPH-induced hyperlocomotion test (AIH), and prepulse inhibition (PPI) of the acoustic startle response in AMPH-sensitized rats.
RESULTS: APH199 caused mild and sporadic anxiolytic and antidepressant effects in EPM and FST, but no remarkable impact on behaviour in other tests in mice. However, we found a significant increase in AMPH-induced hyperactivity, suggesting an exaggeration of the psychotic-like responses in the AMPH-sensitized rats.
CONCLUSIONS: Our data challenged the hypothesis of the therapeutic benefits of DRD4 agonists, pointing out a possible aggravation of psychosis. We suggest a need for further preclinical studies to ensure the safety of antipsychotics with DRD4 stimulating properties.

Matched MeSH terms: Reflex, Startle
Fulltext Gap-induced inhibition of the post-auricular muscle response in humans and guinea pigs

Wilson CA, Berger JI, de Boer J, Sereda M, Palmer AR, Hall DA, et al.

Hear Res, 2019 03 15;374:13-23.
PMID: 30685571 DOI: 10.1016/j.heares.2019.01.009

A common method for measuring changes in temporal processing sensitivity in both humans and animals makes use of GaP-induced Inhibition of the Acoustic Startle (GPIAS). It is also the basis of a common method for detecting tinnitus in rodents. However, the link to tinnitus has not been properly established because GPIAS has not yet been used to objectively demonstrate tinnitus in humans. In guinea pigs, the Preyer (ear flick) myogenic reflex is an established method for measuring the acoustic startle for the GPIAS test, while in humans, it is the eye-blink reflex. Yet, humans have a vestigial remnant of the Preyer reflex, which can be detected by measuring skin surface potentials associated with the Post-Auricular Muscle Response (PAMR). A similar electrical potential can be measured in guinea pigs and we aimed to show that the PAMR could be used to demonstrate GPIAS in both species. In guinea pigs, we compare the GPIAS measured using the pinna movement of the Preyer reflex and the electrical potential of the PAMR to demonstrate that the two are at least equivalent. In humans, we establish for the first time that the PAMR provides a reliable way of measuring GPIAS that is a pure acoustic alternative to the multimodal eye-blink reflex. Further exploratory tests showed that while eye gaze position influenced the size of the PAMR response, it did not change the degree of GPIAS. Our findings confirm that the PAMR is a sensitive method for measuring GPIAS and suggest that it may allow direct comparison of temporal processing between humans and animals and may provide a basis for an objective test of tinnitus.

Matched MeSH terms: Reflex, Startle/physiology*
A successfully treated Dutch case of latah

Jenner JA

J. Nerv. Ment. Dis., 1991 Oct;179(10):636-7.
PMID: 1919550
Matched MeSH terms: Reflex, Startle
Latah: the symbolism of a putative mental disorder

Kenny MG

Cult Med Psychiatry, 1978 Sep;2(3):209-31.
PMID: 710172

This paper examines the symbolic properties and cultural relevance of latah, a behavioral state noted in Malay and Indonesia since the 19th Century. Most interpretations of latah have been psychological, latah being perceived as a 'mental disorder.' In the following, it is concluded that latah is intimately related to other aspects of Malayo-Indonesian culture and that it is a well-known cultural pattern and not a mental disorder as such, though it may occur among persons, largely women, in a socially and psychologically marginal situation. Latah is a symbolic representation of marginality, and it is as appropriate to certain mythological and religious figures to the socially marginal.

Matched MeSH terms: Reflex, Startle
Disease, disorder, or deception? Latah as habit in a Malay extended family

Bartholomew RE

J. Nerv. Ment. Dis., 1994 Jun;182(6):331-8; discussion 339-41.
PMID: 8201305 DOI: 10.1097/00005053-199406000-00004

Thirty-seven cases of latah are examined within the author's Malay extended family (N = 115). Based on ethnographic data collected and a literature review, cases are readily divisible into two broad categories: habitual (N = 33) and performance (N = 4). The first form represents an infrequent, culturally conditioned habit that is occasionally used as a learned coping strategy in the form of a cathartic stress response to sudden startle with limited secondary benefits (i.e., exhibiting brief verbal obscenity with impunity). In this sense, it is identical to Western swearing. Performers are engaged in conscious, ritualized social gain through the purported exploitation of a neurophysiological potential. The latter process is essentially irrelevant, akin to sneezing or yawning. It is concluded that latah is a social construction of Western-trained universalist scientists. The concept of malingering and fraud in anthropology is critically discussed.

Matched MeSH terms: Reflex, Startle