According to a common view, conscious thoughts necessarily involve quasi-perceptual experiences, or mental images. This is alleged to be the case not only when one entertains conscious thoughts about perceptible things, but also when one thinks about more abstract things. In the case of conscious abstract propositional thoughts, the idea is that they occur in inner speech, which is taken to involve imagery (typically auditory) of words in a natural language. I argue that unsymbolized thinking and total aphantasia cast doubt (...) on this common view. Unsymbolized thinking is the experience of thoughts that does not involve imagery. Total aphantasia is the inability to produce mental images of all sensory modalities. I consider and reject the objection that these individuals are mistaken either because their thoughts do involve images, or because those thoughts are not conscious. Thus, unsymbolized thinking and aphantasia provide evidence that conscious thoughts can occur without imagery. (shrink)

Aphantasia is a condition characterised by a deficit of mental imagery. Since several psychopathologies are partially maintained by mental imagery, it may be illuminating to consider the condition against the background of psychological disorder. After outlining current findings and hypotheses regarding aphantasia and psychopathology, this paper suggests that some support for defining aphantasia as a lack of voluntary imagery may be found here. The paper then outlines potentially fruitful directions for future research into aphantasia in general and its relation to (...) psychopathology in particular, including rethinking use of the SUIS to measure involuntary imagery, whether aphantasia offers protection against addiction, and whether hyperphantasia is a potential risk factor for maladaptive daydreaming, among others. (shrink)

Though researchers working on congenital aphantasia (henceforth “aphantasia”) agree that this condition involves an impairment in the ability to voluntarily generate visual imagery, disagreement looms large as to which other impairments are exhibited by aphantasic subjects. This article offers the first extensive review of studies on aphantasia, and proposes that aphantasic subjects exhibit a cluster of impairments. It puts forward a novel cognitive theory of aphantasia, building on the constructive episodic simulation hypothesis of memory and imagination. It argues that aphantasia (...) is best explained as a malfunction of processes in the episodic system, and is therefore an episodic system condition. (shrink)

Experiences that are self-generated and independent of sensory stimulations permeate our whole life. This theme issue examines their similarities and differences, systematizes the literature from an integrative perspective, critically discusses state-of-the-art empirical findings and proposes new theoretical approaches. The aim of the theme issue is to foster interaction between the different disciplines and research directions involved and to explore the prospects of a unificatory account of offline perception in general.

I address the question of whether differences in color terminology cause differences in color experience in speakers of different languages. If linguistic representations directly affect color experience, then this is a case of what I call the linguistic penetrability of perception, which is a particular case of cognitive penetrability. I start with some general considerations about cognitive penetration and its alleged occurrence in the memory color effect. I then apply similar considerations to the interpretation of empirical studies of color perception (...) in speakers of different languages. I argue that findings such as differences in categorical perception in speakers of different languages do not show that language affects color experience. They therefore do not support the claim that color experience is linguistically penetrable. But even if we grant that color experience is different in speakers of different languages, I argue that this might still not be a case of linguistic penetration. Finally, I consider some epistemological consequences of the assumption that speakers of different languages have different color experiences. (shrink)

Several psychological experiments have suggested that concepts can influence perceived color (e.g., Delk and Fillenbaum in Am J Psychol 78(2):290–293, 1965, Hansen et al. in Nat Neurosci 9(11):1367–1368, 2006, Olkkonen et al. in J Vis 8(5):1–16, 2008). Observers tend to assign typical colors to objects even when the objects do not have those colors. Recently, these findings were used to argue that perceptual experience is cognitively penetrable (Macpherson 2012). This interpretation of the experiments has far-reaching consequences: it implies that the (...) way we think of objects determines how we see them, thus threatening the role of perception in justifying beliefs. In this paper, I show that the psychological findings can be accounted for without admitting cognitive penetrability. An underestimated but key feature of the experiments is that observers had to judge colors in borderline cases, in conditions of reduced acuity, or on the basis of color-concepts instead of matching. Such judgments are sensitive to the form of bias that Tversky and Kahneman (Science 185:1124–1131, 1974) have termed ‘anchoring’. Adopting a suggestion from Raffman (Philos Rev 103(1):41–74, 1994), I argue that the way subjects in the experiments think of the objects could affect their color judgments without altering their color experiences. (shrink)

We are prone to gross error, even in favorable circumstances of extended reflection, about our own ongoing conscious experience, our current phenomenology. Even in this apparently privileged domain, our self-knowledge is faulty and untrustworthy. We are not simply fallible at the margins but broadly inept. Examples highlighted in this essay include: emotional experience (for example, is it entirely bodily; does joy have a common, distinctive phenomenological core?), peripheral vision (how broad and stable is the region of visual clarity?), and the (...) phenomenology of thought (does it have a distinctive phenomenology, beyond just imagery and feelings?). Cartesian skeptical scenarios undermine knowledge of ongoing conscious experience as well as knowledge of the outside world. Infallible judgments about ongoing mental states are simply banal cases of self-fulfillment. Philosophical foundationalism supposing that we infer an external world from secure knowledge of our own consciousness is almost exactly backward. (shrink)

Aphantasia is a recently discovered disorder characterised by the total incapacity to generate visual forms of mental imagery. This paper proposes that aphantasia raises important theoretical concerns for the ongoing debate in the philosophy and science of consciousness over the nature of dreams. Recent studies of aphantasia and its neurobehavioral correlates reveal that the majority of aphantasics, whilst unable to produce visual imagery while awake, nevertheless retain the capacity to experience rich visual dreams. This finding constitutes a novel explanandum for (...) theories of dreaming. Specifically, I argue that the recent dream reports of aphantasics constitute an empirical challenge to the emerging family of views which claim that dreams are essentially imaginative experiences, constitutively involving the kinds of mental imagery which aphantasics, ex-hypothesi, lack. After presenting this challenge in the context of Jonathan Ichikawa’s recent arguments for this view, I argue that this empirical challenge may be overcome if the imagination theorist abandons Ichikawa’s account of dreaming in favour of a modified version. This involves the claim that dreams are essentially inactive and constitutively involve non voluntary forms of imagination. I conclude with a suggestion for further research which can test the viability of this alternative hypothesis, and move the debate forward. (shrink)

Historically, mental imagery has been defined as an experiential state - as something necessarily conscious. But most behavioural or neuroimaging experiments on mental imagery - including the most famous ones - don’t actually take the conscious experience of the subject into consideration. Further, recent research highlights that there are very few behavioural or neural differences between conscious and unconscious mental imagery. I argue that treating mental imagery as not necessarily conscious (as potentially unconscious) would bring much needed explanatory unification to (...) mental imagery research. It would also help us to reassess some of the recent aphantasia findings inasmuch as at least some subjects with aphantasia would be best described as having unconscious mental imagery. (shrink)

Lucid dreaming refers to a dream state characterized by the dreamers awareness of being in a dream and being able to volitionally control its content. The aim of this study was to find neurophysiological evidence for the 7 criteria of lucid dreaming proposed by Paul Tholey. Each of the criteria was analyzed separately with regard to its underlying neurocircuits. We hypothesized that not one, but many regions are involved in the state of lucid dreaming. Our results have shown a satisfactory (...) overlap of the theoretical components and the brain regions activated during a lucid dream. During lucid dreaming, a brain network seems to emerge, that is more than the sum of its parts. Further research is needed to understand the psychoneurological underpinnings of lucid dreams. (shrink)

As awareness of the phenomenon of aphantasia (= lack of voluntary imagery) has increased in recent years, many psychotherapists ponder its clinical implications. The present study investigates whether aphantasia meets the criteria for mental disorders, i.e. statistical rarity, impairment in activities of daily living, violation of social norms and inappropriate behavior and personal distress. Prevalence of aphantasia was determined meta-analytically based on 3,543 participants. An international sample of 156 participants with aphantasia (58.3% male; Mage = 35.23) and 131 controls (65.6% (...) male; Mage = 28.88) was assessed with the Reading the Mind in the Eyes Test, the Questionnaire for the Assessment of Everyday Memory Performance and the Aphantasia Distress Questionnaire, as well as measures of depression, anxiety and well-being. The prevalence of aphantasia was estimated at 3.5 to 4.8%. Participants with aphantasia scored significantly lower than controls on every day and autobiographical memory, but not on theory of mind. A subgroup of 34.7% of participants with aphantasia reported distress significantly associated with lower well-being and high levels of anxiety and depression. The level of distress increased with poorer performance in autobiographical memory and theory of mind. Although aphantasia meets the criterion of statistical rarity, the impact on activities of daily living and personal distress is too weak to justify a classification as a mental disorder. In a subgroup, however, distress can reach clinically relevant levels. In individual cases, it is therefore advisable to conduct a psychological assessment, for example by means of the Aphantasia Distress Questionnaire. (shrink)

There is mounting evidence that language comprehension involves the activation of mental imagery of the content of utterances (Barsalou, 1999;Bergen, Chang, & Narayan, 2004;Bergen, Narayan, & Feldman, 2003;Narayan, Bergen, & Weinberg, 2004;Richardson, Spivey, McRae, & Barsalou, 2003;Stanfield & Zwaan, 2001;Zwaan, Stanfield, & Yaxley, 2002). This imagery can have motor or perceptual content. Three main questions about the process remain under‐explored, however. First, are lexical associations with perception or motion sufficient to yield mental simulation, or is the integration of lexical semantics (...) into larger structures, like sentences, necessary? Second, what linguistic elements (e.g., verbs, nouns, etc.) trigger mental simulations? Third, how detailed are the visual simulations that are performed? A series of behavioral experiments address these questions, using a visual object categorization task to investigate whether up‐ or down‐related language selectively interferes with visual processing in the same part of the visual field (followingRichardson et al., 2003). The results demonstrate that either subject nouns or main verbs can trigger visual imagery, but only when used in literal sentences about real space—metaphorical language does not yield significant effects—which implies that it is the comprehension of the sentence as a whole and not simply lexical associations that yields imagery effects. These studies also show that the evoked imagery contains detail as to the part of the visual field where the described scene would take place. (shrink)