Social-emotional agnosia

Last updated

Social-emotional agnosia, also known as emotional agnosia or expressive agnosia, is the inability to perceive facial expressions, body language, and voice intonation. [1] A person with this disorder is unable to non-verbally perceive others' emotions in social situations, limiting normal social interactions. The condition causes a functional blindness to subtle non-verbal social-emotional cues in voice, gesture, and facial expression. People with this form of agnosia have difficulty in determining and identifying the motivational and emotional significance of external social events, and may appear emotionless or agnostic (uncertainty or general indecisiveness about a particular thing). Symptoms of this agnosia can vary depending on the area of the brain affected. Social-emotional agnosia often occurs in individuals with schizophrenia and autism. It is difficult to distinguish from, and has been found to co-occur with, alexithymia. [2]

Contents

Presentation

Damage to the right temporal occipital region in humans has been associated with the inability to recognize the faces of loved ones, friends, and pets (considered a form of prosopagnosia).[ citation needed ] This limits the ability to appropriately interact with familiar people, potentially severely damaging interpersonal relationships. People with social-emotional agnosia may distance themselves from interacting with other people and prefer isolation. Maternal behavior is also severely affected, causing mothers to fail to recognize their children as their own. [3] In human children, deficits in imitating and responding to peer social interactions have been observed. Children with this agnosia have also been found to have hyperorality, an increased tendency to investigate objects with their mouths, which is also a common symptom of Klüver–Bucy syndrome. [4]

Causes

Social-emotional agnosia is mainly caused by abnormal functioning in a particular brain area called the amygdala. Typically this agnosia is only found in people with bilateral amygdala damage; that is damage to amygdala regions in both hemispheres of the brain.[ citation needed ] It can be accompanied by right or bilateral temporal lobe damage. The amygdala dysfunction causes the inability to select appropriate behaviors in a specific social context. Symptoms can include reduced aggression, fearfulness, competitiveness, and social dominance. [5] Those with social-emotional agnosia have difficulty discerning the emotional meaning and significance behind objects, which causes a loss of fondness and familiarity. Bilateral amygdala damage has also been associated with social unresponsiveness, leading to an avoidance of social interactions and a preference for isolation from their own species. Evidence suggests that damage to the amygdala and the limbic system (specifically the amygdala-hypothalamus pathway) results in the loss of the core ability to recognize and interpret the mental states of others, a vital ability in social interactions. [5] The amygdala evokes highly personal emotional memories and the loss of this function causes hypo-emotionality, a general lack of emotion when presented with different stimuli.[ citation needed ] Hypersexuality has also been observed in those with disconnection in the amygdala-hypothalamus pathway.[ citation needed ] Temporal lobe epilepsy has been shown to cause bilateral amygdala damage which could result in symptoms similar to social-emotional agnosia, but the precise relationship between the two disorders is unknown.[ citation needed ]

Diagnosis

Classification

Social-emotional agnosia is generally diagnosed through the use of two tests, the Faux Pas Test and the Strange Stories Test. Both of these tests are used to show deficits in theory of mind, the recognition of mental states of others. For people with social-emotional agnosia, it is mainly the emotional states that are difficult for them to recognize. Studies have shown that subjects with amygdala damage perform poorly on both the Faux Pas test and the Strange Stories test. [6]

Faux Pas test

The Faux Pas test measures how socially adept one is in certain situations. For this test, a faux pas is considered a statement or action that accidentally offends another person. During the test, the subject or patient is told of various social situations and later asked if one of the people in the story would be offended in the situation. A person with impaired social skills would have difficulty in detecting the faux pas made by characters in the stories.[ citation needed ]

Strange Stories test

The emotional aspect of social-emotional agnosia is usually assessed with the Strange Stories test. The subject or patient is presented with two sets of stories: social stories that refer to people's emotional states and physical stories that refer to physical behaviors. Those with deficits in determining others' emotional states will answer questions regarding the emotional stories incorrectly but will answer questions regarding the physical stories correctly (showing that their comprehension of the stories is not impaired but instead that their comprehension of emotional states in others is impaired).[ citation needed ]

Other tests

Another test that could be used to diagnose emotional deficits is the Facial Recognition Test, where subjects are presented a number of pictures of faces with a variety of expressions, and are asked to determine what emotion they are depicting. [7]

Differential diagnosis

The constellation of symptoms in social-emotional agnosia can also be seen in a number of different behavioral disorders.[ citation needed ]

Autism or Asperger's syndrome

Both autism and Asperger's syndrome show deficits in understanding others' mental states, including the recognition of emotional expressions. Damage to the amygdala has also been implicated for these disorders, which can explain why the symptoms appear to overlap. [3]

Klüver–Bucy syndrome

Although rare in humans, Klüver–Bucy syndrome has many symptoms that are strikingly similar to those seen in social-emotional agnosia. The amygdala and temporal lobes have been implicated in the pathology of Klüver–Bucy syndrome as well, leading to docility, hyperorality, and in some rare cases hypersexuality. Unlike patients of social-emotional agnosia, people with Klüver–Bucy syndrome also tend to demonstrate visual agnosia (inability to recognize visual stimuli) and have difficulties with visual perception. [4]

Research

Numerous studies with rhesus monkeys have been performed to see the effects of bilateral amygdala removal. In rhesus monkeys, bilateral destruction of the amygdala has been shown to significantly disturb the ability to behave in a socially normal manner with deficits in detecting the motivational and emotional states of other monkeys. Monkeys with amygdala damage that are reintroduced to their colony willfully exclude themselves from social interaction and isolate themselves from the group. Primate mothers with amygdala lesions appear to lose maternal affection towards their offspring. They seem to consider the offspring a foreign object, sometimes going so far as to harm or throw around the juvenile monkeys.[ citation needed ]

There have been additional studies with rhesus monkeys researching Klüver–Bucy syndrome, which shows similar pathologies and symptoms to social-emotional agnosia (see Related disorders for human comparison). Monkeys with Klüver–Bucy syndrome demonstrated a loss of fear and aggression, hyperorality, and hypersexuality. Unlike the previously mentioned studies regarding amygdala lesions, these monkeys demonstrated problems with visual perception. [4]

Related Research Articles

<span class="mw-page-title-main">Amygdala</span> Each of two small structures deep within the temporal lobe of complex vertebrates

The amygdala is one of two almond-shaped clusters of nuclei located deep and medially within the temporal lobes of the brain's cerebrum in complex vertebrates, including humans. Shown to perform a primary role in the processing of memory, decision making, and emotional responses, the amygdalae are considered part of the limbic system. The term "amygdala" was first introduced by Karl Friedrich Burdach in 1822.

<span class="mw-page-title-main">Limbic system</span> Set of brain structures involved in emotion and motivation

The limbic system, also known as the paleomammalian cortex, is a set of brain structures located on both sides of the thalamus, immediately beneath the medial temporal lobe of the cerebrum primarily in the forebrain.

Hypersexuality is extremely frequent or suddenly increased libido. It is controversial whether it should be included as a clinical diagnosis used by mental healthcare professionals. Nymphomania and satyriasis were terms previously used for the condition in women and men, respectively.

<span class="mw-page-title-main">Temporal lobe</span> One of the four lobes of the mammalian brain

The temporal lobe is one of the four major lobes of the cerebral cortex in the brain of mammals. The temporal lobe is located beneath the lateral fissure on both cerebral hemispheres of the mammalian brain.

<span class="mw-page-title-main">Brodmann area 38</span>

Brodmann area 38, also BA38 or temporopolar area 38 (H), is part of the temporal cortex in the human brain. BA 38 is at the anterior end of the temporal lobe, known as the temporal pole.

<span class="mw-page-title-main">Limbic lobe</span> Region of a cerebral cortex

The limbic lobe is an arc-shaped region of cortex on the medial surface of each cerebral hemisphere of the mammalian brain, consisting of parts of the frontal, parietal and temporal lobes. The term is ambiguous, with some authors including the paraterminal gyrus, the subcallosal area, the cingulate gyrus, the parahippocampal gyrus, the dentate gyrus, the hippocampus and the subiculum; while the Terminologia Anatomica includes the cingulate sulcus, the cingulate gyrus, the isthmus of cingulate gyrus, the fasciolar gyrus, the parahippocampal gyrus, the parahippocampal sulcus, the dentate gyrus, the fimbrodentate sulcus, the fimbria of hippocampus, the collateral sulcus, and the rhinal sulcus, and omits the hippocampus.

Witzelsucht is a set of pure and rare neurological symptoms characterized by a tendency to make puns, or tell inappropriate jokes or pointless stories in socially inappropriate situations. It makes one unable to read sarcasm.

Auditory verbal agnosia (AVA), also known as pure word deafness, is the inability to comprehend speech. Individuals with this disorder lose the ability to understand language, repeat words, and write from dictation. Some patients with AVA describe hearing spoken language as meaningless noise, often as though the person speaking was doing so in a foreign language. However, spontaneous speaking, reading, and writing are preserved. The maintenance of the ability to process non-speech auditory information, including music, also remains relatively more intact than spoken language comprehension. Individuals who exhibit pure word deafness are also still able to recognize non-verbal sounds. The ability to interpret language via lip reading, hand gestures, and context clues is preserved as well. Sometimes, this agnosia is preceded by cortical deafness; however, this is not always the case. Researchers have documented that in most patients exhibiting auditory verbal agnosia, the discrimination of consonants is more difficult than that of vowels, but as with most neurological disorders, there is variation among patients.

<span class="mw-page-title-main">Hippocampal formation</span> Region of the temporal lobe in mammalian brains

The hippocampal formation is a compound structure in the medial temporal lobe of the brain. It forms a c-shaped bulge on the floor of the temporal horn of the lateral ventricle. There is no consensus concerning which brain regions are encompassed by the term, with some authors defining it as the dentate gyrus, the hippocampus proper and the subiculum; and others including also the presubiculum, parasubiculum, and entorhinal cortex. The hippocampal formation is thought to play a role in memory, spatial navigation and control of attention. The neural layout and pathways within the hippocampal formation are very similar in all mammals.

<span class="mw-page-title-main">Frontal lobe disorder</span> Brain disorder

Frontal lobe disorder, also frontal lobe syndrome, is an impairment of the frontal lobe that occurs due to disease or frontal lobe injury. The frontal lobe of the brain plays a key role in executive functions such as motivation, planning, social behaviour, and speech production. Frontal lobe syndrome can be caused by a range of conditions including head trauma, tumours, neurodegenerative diseases, Neurodevelopmental disorders, neurosurgery and cerebrovascular disease. Frontal lobe impairment can be detected by recognition of typical signs and symptoms, use of simple screening tests, and specialist neurological testing.

Klüver–Bucy syndrome is a syndrome resulting from bilateral lesions of the medial temporal lobe. Klüver–Bucy syndrome may present with compulsive eating, hypersexuality, insertion of inappropriate objects in the mouth (hyperorality), visual agnosia, and docility. Klüver–Bucy syndrome is more commonly found in rhesus monkeys, where the condition was first documented, than in humans. Pathology on the syndrome is still controversial with Norman Geschwind's theory and Muller theory offering different explanations for the condition. Treatment for Klüver–Bucy syndrome is minimal with no current cure.

<span class="mw-page-title-main">Cortical deafness</span> Medical condition

Cortical deafness is a rare form of sensorineural hearing loss caused by damage to the primary auditory cortex. Cortical deafness is an auditory disorder where the patient is unable to hear sounds but has no apparent damage to the anatomy of the ear, which can be thought of as the combination of auditory verbal agnosia and auditory agnosia. Patients with cortical deafness cannot hear any sounds, that is, they are not aware of sounds including non-speech, voices, and speech sounds. Although patients appear and feel completely deaf, they can still exhibit some reflex responses such as turning their head towards a loud sound.

Paul Bucy was an American neurosurgeon and neuropathologist who was a native of Hubbard, Iowa. He is known both for his part in describing the Klüver–Bucy syndrome, his academic life as a teacher in the neurosciences, and for his founding in 1972 and editing Surgical Neurology – An International Journal of Neurosurgery and Neuroscience" from 1972 to 1987.

<span class="mw-page-title-main">Neurological disorder</span> Any disorder of the nervous system

A neurological disorder is any disorder of the nervous system. Structural, biochemical or electrical abnormalities in the brain, spinal cord or other nerves can result in a range of symptoms. Examples of symptoms include paralysis, muscle weakness, poor coordination, loss of sensation, seizures, confusion, pain and altered levels of consciousness. There are many recognized neurological disorders, some relatively common, but many rare. They may be assessed by neurological examination, and studied and treated within the specialities of neurology and clinical neuropsychology.

<span class="mw-page-title-main">Urbach–Wiethe disease</span> Rare recessive genetic disorder

Urbach–Wiethe disease is a very rare recessive genetic disorder, with approximately 400 reported cases since its discovery. It was first officially reported in 1929 by Erich Urbach and Camillo Wiethe, although cases may be recognized dating back as early as 1908.

Charcot–Wilbrand syndrome (CWS) describes dream loss following focal brain damage specifically characterised by visual agnosia and loss of ability to mentally recall or "revisualize" images. The name of this condition dates back to the case study work of Jean-Martin Charcot and Hermann Wilbrand, and was first described by Otto Potzl as "mind blindness with disturbance of optic imagination". MacDonald Critchley, former president of the World Federation of Neurology, more recently summarized CWS as "a patient loses the power to conjure up visual images or memories, and furthermore, ceases to dream during his sleeping hours". This condition is quite rare and affects only a handful of brain damage patients. Further study could help illuminate the neurological pathway for dream formation.

Phonagnosia is a type of agnosia, or loss of knowledge, that involves a disturbance in the recognition of familiar voices and the impairment of voice discrimination abilities in which the affected individual does not suffer from comprehension deficits. Phonagnosia is an auditory agnosia, an acquired auditory processing disorder resulting from brain damage, other auditory agnosias include cortical deafness and auditory verbal agnosia also known as pure word deafness.

S.M., also sometimes referred to as SM-046, is an American woman with a peculiar type of brain damage that prevents her from experiencing fear. First described by scientists in 1994, she has had exclusive and complete bilateral amygdala destruction since late childhood as a consequence of Urbach–Wiethe disease. Dubbed by the media as the "woman with no fear", S.M. has been studied extensively in scientific research; she has helped researchers elucidate the function of the amygdala.

Nonverbal autism is a subset of autism where the person does not learn how to speak. It is estimated that 25% to 50% of children diagnosed with autism spectrum disorder (ASD) never develop spoken language beyond a few words or utterances.

Amygdalotomy is a form of psychosurgery which involves the surgical removal or destruction of the amygdala, or parts of the amygdala. It is usually a last-resort treatment for severe aggressive behavioral disorders and similar behaviors including hyperexcitability, violent outbursts, and self-mutilation. The practice of medical amygdalotomy typically involves the administration of general anesthesia and is achieved through the application of cranial stereotactic surgery to target regions of the amygdala for surgical destruction. While some studies have found stereotactic amygdalotomy in humans to be an effective treatment for severe cases of intractable aggressive behavior that has not responded to standard treatment methods, other studies remain inconclusive. In most cases of amygdalotomy in humans, there is no substantial evidence of impairment in overall cognitive function, including intelligence and working memory, however, deficits in specific areas of memory have been noted pertaining to the recognition and emotional interpretation of facial stimuli. This is because there are specialized cells in the amygdala which attend to facial stimuli.

References

  1. ↑ "Medical Education for Undergraduate MD Students ." Agnosia. N.p., 14 Apr 2011. Web. 28 Nov 2011.
  2. ↑ Schmitz, Bettina, and Michael Trimble. The Neuropsychiatry of Epilepsy. 1st. London: Cambridge University Press, 2002: 110-111.
  3. 1 2 Baron-Cohen, S.; Ring, H.A.; Bullmore, E.T.; Wheelwright, S.; Ashwin, C.; Williams, S.C.R. (2000). "The amygdala theory of autism". Neuroscience & Biobehavioral Reviews. 24 (3): 355–364. doi:10.1016/s0149-7634(00)00011-7. PMID   10781695. S2CID   7455984.
  4. 1 2 3 Salloway, Stephen, Paul Mallory, and Jeffrey L. Cummings. The neuropsychiatry of limbic and subcortical disorders. 1997.
  5. 1 2 Amaral, D. G.; Corbett, B. A. (2003). "The amygdala, autism and anxiety". Novartis Foundation Symposium. 251: 177–87, discussion 187-97, 281–97. PMID   14521193.
  6. ↑ Schmitz, Bettina, and Michael Trimble. The Neuropsychiatry of Epilepsy. 1st. London: Cambridge University Press, 2002: 114-115.
  7. ↑ Stone, Valerie E.; Baron-Cohen, Simon; Knight, Robert T. (1998). "Frontal Lobe Contributions to Theory of Mind" (PDF). Journal of Cognitive Neuroscience. 10 (5): 640–656. doi:10.1162/089892998562942. PMID   9802997. S2CID   207724498.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.