Lateralized Visual Hallucinations: An Analysis of Affective Valence

Abstract

Visual formaesthesias (hallucinations) are a common symptom of neurological insult. Research on emotional valances and the laterality of emotional valence extends to clinical populations experiencing visual hallucinations. The purpose of this project was to evaluate the relationship of reported hemispace of visual formaesthesia and associated emotional valence. Based on current literature exploring asymmetries in the processing of emotional valence, it was predicted that right visual formaesthesias would be predominantly associated with positive emotion and that left visual formaesthesias would largely be associated with negative emotion. Review of archival data on 150 neuropsychological patients from a rehabilitation unit in a tertiary care regional medical center resulted in 25 men and women, ages 25 to 93, endorsing visual formaesthesia upon neuropsychological interview. Analysis of variance results indicate the associated affective valence of the visual formaesthesia is a function of location, F(1, 24) = 8.33, p < .008. Additionally, the majority (84%) of sensory deficits detected were left-sided, regardless of the location of the formaesthesia. Patients specifically evidencing visual and tactile deficits had essentially exclusive left-sided deficits regardless of the location of the formaesthesia.

Behavioral Consequences and Cortical Reorganization in Homonymous Hemianopia

“…Thus, the fact that only patients with right-side lesions reported visual hallucinations suggests an effect of the lesion side on the occurrence of hallucinatory phenomena. Thus, we propose that the side of the occipital lesion determines the occurrence of visual hallucinations whereas the visual field of apparition influences the emotional valence, with more frequent hallucinations in the blind, contralesional visual field than in the ipsilesional visual field, as reported in the previously cited study by Walters et al (2006) Regardless, further studies are necessary to elucidate the link between the lesion side, the visual field of apparition and the various parameters of visual hallucinations (nature, frequency, severity, similarity with mental imagery, emotional valence, etc.). Interestingly, preliminary results from one of our group’s current studies using the Q3H questionnaire suggest that the occurrence and type of visual hallucinations in hemianopic patients might also depend on the extent of the lesion.…”

“…Over the past 5 years, our group and others have suggested that the side of the occipital lesion might be an important factor in the nature and severity of visual impairments in hemianopic patients. Similarly, Walters et al (2006) investigated whether complex visual hallucinations caused by an occipital lesion might be linked to the lesion side and to patients’ emotional valence. In their study, they systematically searched for hallucinations in left or right brain-damaged patients and recorded the side of the hallucination, as well as its emotional valence.…”

Brain and Psyche in Early Christian Asceticism

“…1. Prefrontal cortex in the right cerebral hemisphere is dominant in depressed mood and withdrawal-related emotion (van Honk & Schutter, 2006;Walters, Harrison, Williamson, & Foster, 2006;Herrington, Heller, Engels, Baniach, Webb, & Miller, 2010). Left prefrontal cortex has an analogous role with respect to positive, approach-oriented emotion.…”

“…Spatial coordinates continue to have moral or at least emotional meanings at the present time (seeWalters, Harrison, Williamson, & Foster, 2006;Tamagni, Mantei, & Brugger, 2009).…”

Emotion and space: lateralized emotional word detection depends on line bisection bias

“…As a rule, damage to (anterior) regions of the LH induces negative affect, depression or even elicits "catastrophic reactions", while comparable damage to the right hemisphere may rather lead to enhanced positive mood, anosodiaphoria (i.e., marked downplaying of the consequences of an illness) and mania-like, euphoric reactions (Davidson, 1995;Gainotti, 1972;Silberman and Weingartner, 1986). Also, unilateral hallucinations after brain damage are experienced as emotionally negative when occurring in the left visual field (LVF), while those in the right visual field (RVF) are of predominantly positive content (Walters et al, 2006;Mollet et al, 2007). Even in not strictly lateralized psychiatric disorders, the degree of negativity of hallucinatory experiences correlates with specifically RH involvement, both in the auditoryverbal (Sommer et al, 2008) and somesthetic domain (Brugger, 2007).…”