Lecture 4 definitions Flashcards
Phenomenal (basic) consciousness
Related to feelings, sensations and orienting to the present moment
Higher consciousness
Related to the ability to reason, reflect on one’s experiences, and have a sense of self. It’s debated whether this level of consciousness is only available to humans or also to other animals.
Reticular activating system
Critical for the maintenance of our consciousness
Controlled (conscious/explicit) processing
The conscious use of attention and the effort put into that specific action. It is slower, but more flexible (e.g., learning how to drive)
Automatic (unconscious/implicit) processing
Activities that can be performed without conscious awareness or effort (e.g., walking, riding a bike). This type of processing facilitates divided attention.
The cocktail party problem
Refers to issues such as how do we focus on one speaker (and ignore others) in a room full of speakers? It concerns selective attention and sound segregation
Dichotic listening task
Introduced by Broadbent. Participants are given a pair of headphones with two channels. They are supposed to replicate one of the channels’ input out loud, and are afterwards asked to recall as much information as possible from the ignored input. Broadbent argues that physical features are often recalled (such as whether the voice was feminine or masculine), but the content is usually lost.
Filter model
Broadbent proposed that multiple inputs are filtered based on physical properties to select the most relevant ones. Hence, meaning is processed after the filtering stages. A limitation of the model is that it predicts that you should not be able to detect salient information from ignored channels (e.g., other speakers in the cocktail party), yet you are able to shift attention if an ignored speaker says something interesting (such as your name).
Top-down modulation
Enhances input based on relevance (i.e., to tasks such as conversing with 1 individual at a party, while distracting input/other voices are suppressed) and expectation (expected physical features of the other person’s voice, the content of their sentences, etc.) Bottom-up signals can still win out, but require more salience. This can be required through intensity (loud noise, bright flash, etc.) or arousal (hearing one’s own name)
Visual Agnosia
Patient DF could not consciously visually perceive the shape, size or orientation of objects. An example is the man in the video holding deodorant and being unsure whether it is toothpaste or not and what to do with it. In this case, the visual information could not be bound together. This is caused by bilateral lesions to early ventral visual stream, which deals with object shape and identity.
Prosopagnosia
Referring to face blindness, meaning that patients can recognise objects but not faces. It is caused by damage to inferotemporal cortex (late ventral stream).
Optic ataxia
Difficulty in using visual information to guide actions that cannot be ascribed to motor, somatosensory, visual field or acuity deficits. It deficits with the”how/where” stream, but not the “what” stream (where you recognise objects)
Blindsight
Damage to primary visual cortex results in cortical blindness. However, while patients cannot see and identify objects, they can often respond correctly to features of that object (motion, orientation, etc)
Priming
An effect where presentation of a subliminal stimulus influences subsequent behaviour (e.g., judgements). For example, if you flash the word ‘happiness’ very quickly and afterwards ask respondents how they feel about a certain image, they will respond more positive, even though the respondent did not actively process the word happiness. Associative priming occurs when a subliminally presented object (such as a word) improves recognition of a subsequent object. For example, presenting the word “FOOT” positively influences how you feel about the word “SHOE”, but not another word like “BREAD”.
EEG
Measures brain activity
EMG
Measures muscle activity
EOG
Measures eye activity
REM sleep
Stands for rapid eye movement. It is characterised by eye movement, high arousal (similar to waking state) and frequent dreaming. It is also called paradoxical sleep, as the EEG pattern is similar to the awake state, but EMG (muscle) activity is low.
REM sleep paralysis
State where we cannot engage voluntary muscles
Slow-wave sleep
Brain waves become slower as sleep gets deeper. Stages 3 and 4 are referred to as slow-wave sleep
What happens during the course of the night while sleeping?
REM patterns increase in length, while stages 3 & 4 (slow-wave sleep) decrease in length. The sleep pattern repeats approximately every 90 minutes.
Which parts of the brain are involved while falling asleep?
The basal forebrain, areas of the brainstem (especially the pontine reticular activating system). The Limbic system and association areas are highly active during REM sleep. The motor cortex is also active, but its signals to the PNS are blocked. There is also a decreased activity in the prefrontal cortex.
How does sleep change across our lifespan?
Elderly adults sleep just under 6 hours on average. REM sleep decreases dramatically during infancy and childhood but remains stable thereafter. Time spent in stage 3 and 4 decline with age.
What is the importance of sleep?
Both REM and deep states are critical for us to consolidate (store long-term) memories we make during the day. Our brain is likely replaying the activation patterns of our recent experiences, and embedding them into existing associative networks. This process may also be important for forgetting existing memories or associations.
