Imagination Flashcards
Neural correlates of imagination
What is the Default Mode Network (DMN)?
A system for internal and ‘self-focused’ mental processes
Active in resting state and shows consistent deactivation patterns across tasks that require external focus.
Neural correlates of imagination
What mental processes are associated with increased activity in the DMN?
- Self-referential processing
- Social cognition
- Episodic memory operations
- Language and semantic memory
- Spontaneous thoughts, mind wandering, daydreaming
Neural correlates of imagination
How does the DMN relate to imagination?
Enables the brain to ‘decouple’ from immediate sensory inputs and direct attention inward
Divergent thinking (creative cognition) heavily involves the DMN
Memory provides the content for imagination and involves recombining knowledge structures:
semantic memory = conceptual content
episodic memory = scene construction, imagining hypothetical events through time
Define imagination.
The act or power of forming a mental representation of something not present to the senses or never before wholly perceived in reality.
What is the constructive episodic simulation hypothesis?
Imagining future events is based on recombining episodic memories of past experiences.
What role does semantic memory play in imagination?
Provides conceptual content for imaginative processes.
What is mental time travel?
The faculty that allows humans to mentally project themselves backwards in time to re-live, or forwards to pre-live, events.
Doubts: a parallel relationship of recollection and imagination? a parsimonious relationship? Is the future we project truly ‘future’?
What two factors influence the phenomenological characteristics of constructed scenarios in recollections and imaginations?
- The valence of the event
- The temporal distance from the present
positive past and future events both rated with more vivid phenomenal characteristics
decrease in phenomenal richness of both past and future episodes with their increased temporal distance from the present
(Skepticism of) Mental time travel
What brain regions are part of the common network activated during remembering the past and imagining the future?
- Posterior cingulate cortex
- Precuneus
- Angular gyrus
- Middle, superior, and inferior frontal gyri
- Hippocampus
(angular gyrus?)
- active during concious resting state
- closely connected to one’s feeling of self
Remembering the past and imagining the future (mental time travel) assoicated with frontal and temporal lobe activity
(Skepticism of) Mental time travel
True or False: Mental time travel only applies to past recollections.
False
It also includes imagining future events.
Dynamics of top-down/bottom-up processes
What is multisensory integration?
When information from different sensory modalities is combined to create a unified and coherent perceptual experience.
Percpetion is seen as an interaction between top-down, generated and bottom-up data driven processes
–> what is subjectively experienced (perception) is an internal representation of the external sensory world (hallucinations and imagination)
Dynamics of top-down/bottom-up processes
Describe the dynamic interaction between top-down and bottom-up processes in perception and imagination.
Perception relies on bottom-up signals to process external input but integrates top-down modulation to interpret ambiguous or incomplete data.
vs
Imagination is predominantly top-down but often incorporates bottom-up elements through sensory memory
top-down modulation can shape multisensory integration, enhancing percpetual coherence in ambiguous environments (Choi et al (2018))
Dynamics of top-down/bottom-up processes
What brain structures are involved? What is their function and role?
- Primary sensory cortices (V1, A1)
function = inital processing of visual and auditory information
role = reactivated during imagery tasks, indicating shared pathways with perception - Prefrontal cortex
function = executive control, working memory, attention
role = orchestrates top-down modulation by directing attention and selecting memory fragments for imaginative tasks. - Hippocampus
function = memory encoding and retrieval
role = support imagination by integrating episodic memory into cohesive scenarios - Parietal cortex
function = spatial integration and sensory-motor coordination
role = facilitates spatial coherence in imagined scenes - Thalamus
function = relay station for sensory information
role = filters bottom-up input and integrates it with top-down signals for coherent perception and imagination
Other networks:
1) default mode network
2) Frontoparietal network = balances top-down and bottom-up processes, ensuring coherence in perception and imagination
Dynamics of top-down/bottom-up processes
What distinguishes hallucinations from illusions?
Hallucinations are involuntary sensory percepts occurring without external stimuli, while illusions (voluntary?) involve misperceptions of something that is actually present.
visual imagery and visual hallucinations may be different expressions of the same or similar underlying neurobiological mechanism
Dysfunctions of Imagination
What is the Perky effect?
When visual mental imagery interferes with actual perception, often without conscious awareness.
- while imagining an object and at the same time being exposed to a faint image or similar object may lead participants to confuse the real object with their imagination (often entirely attributed to imagination)
- mental imagery reduces visual acuity in taks involving fine spatial details (especially when overlap between imagination and actual stimulus)
- interference from mental imagery is not confined to the specific location of the imagined object –> extends spatially, affects nearby areas
