Alpha oscillations are ubiquitous in the brain, but their role in cortical processing remains a matter of debate. Recently, evidence has begun to accumulate in support of a role for alpha oscillations in attention selection and control. Here we first review evidence that 8-12 Hz oscillations in the brain have a general inhibitory role in cognitive processing, with an emphasis on their role in visual processing. Then, we summarize the evidence in support of our recent proposal that alpha represents a pulsed-inhibition of ongoing neural activity. The phase of the ongoing electroencephalography can influence evoked activity and subsequent processing, and we propose that alpha exerts its inhibitory role through alternating microstates of inhibition and excitation. Finally, we discuss evidence that this pulsed-inhibition can be entrained to rhythmic stimuli in the environment, such that preferential processing occurs for stimuli at predictable moments. The entrainment of preferential phase may provide a mechanism for temporal attention in the brain. This pulsed inhibitory account of alpha has important implications for many common cognitive phenomena, such as the attentional blink, and seems to indicate that our visual experience may at least some times be coming through in waves.

/pdf/pulsed-out-of-awareness-eeg-alpha-oscillations-represent-a-4j9j5cn4nx.pdf

心理学原理 = The principles of psychology

Pulsed out of awareness: EEG alpha oscillations represent a pulsed-inhibition of ongoing cortical processing

Summary This paper reviews disorders of memory. After a brief survey of the clinical varieties of the amnesic syndrome, transient and persistent, selected theoretical issues will be considered by posing a series of questions. (i) What is impaired and what is spared in anterograde amnesia? (ii) Do temporal lobe, diencephalic and frontal lobe amnesias differ? (iii) How independently semantic is semantic memory? (iv) What determines the pattern and extent of retrograde memory loss? (v) Can retrograde amnesia ever be ‘isolated’? (vi) Does psychogenic amnesia involve the same mechanisms as organic amnesia? (vii) How and when do false memories arise? Commonalities as well as differences across separate literatures will be emphasized, and the case for a more ‘dynamic’ (interactionist) approach to the investigation of amnesia will be advocated.

Disorders of memory

During brief, dangerous events, such as car accidents and robberies, many people report that events seem to pass in slow motion, as if time had slowed down. We have measured a similar, although less dramatic, effect in response to unexpected, nonthreatening events. We attribute the subjective expansion of time to the engagement of attention and its influence on the amount of perceptual information processed. We term the effect time's subjective expansion (TSE) and examine here the objective temporal dynamics of these distortions. When a series of stimuli are shown in succession, the low-probability oddball stimulus in the series tends to last subjectively longer than the high-probability stimulus even when they last the same objective duration. In particular, (1) there is a latency of at least 120 msec between stimulus onset and the onset of TSE, which may be preceded by subjective temporal contraction; (2) there is a peak in TSE at which subjective time is particularly distorted at a latency of 225 msec after stimulus onset; and (3) the temporal dynamics of TSE are approximately the same in the visual and the auditory domains. Two control experiments (in which the methods of magnitude estimation and stimulus reproduction were used) replicated the temporal dynamics of TSE revealed by the method of constant stimuli, although the initial peak was not apparent with these methods. In addition, a third, control experiment (in which the method of single stimuli was used) showed that TSE in the visual domain can occur because of semantic novelty, rather than image novelty per se. Overall, the results support the view that attentional orienting underlies distortions in perceived duration.

/pdf/attention-and-the-subjective-expansion-of-time-2ldcj4oa9a.pdf

Attention and the subjective expansion of time.

Sociometer theory proposes that the self-esteem system evolved as a monitor of social acceptance, and that the so-called self-esteem motive functions not to maintain self-esteem per se but rather to avoid social devaluation and rejection. Cues indicating that the individual is not adequately valued and accepted by other people lower self-esteem and motivate behaviors that enhance relational evaluation. Empirical evidence regarding the self-esteem motive, the antecedents of self-esteem, the relation between low self-esteem and psychological problems, and the consequences of enhancing self-esteem is consistent with the theory.

https://instruct.uwo.ca/psychology/371g/Leary1999.pdf

Making Sense of Self-Esteem

Imagine walking down a supermarket aisle and passing an end-of-aisle display of canned tomato soup. A sign on the display says, “Limit 12 per customer.” Would such a sign influence the number of cans you would buy? Would you buy more cans than if the sign said “No limit per customer”? Our intuitions say no, but empirical evidence indicates that purchase behaviors are influenced by such a sign (Wansink, Kent, & Hoch, 1998). Consider another example: A wheel of fortune is spun and stops at the number 65. You are then asked if the percentage of African countries in the United Nations is above or below that number. Could this exercise influence your estimate of the relevant percentage? Although it may seem unlikely, the evidence is that such anchors have an effect: Groups who received larger numbers determined by a wheel of fortune gave higher estimates than groups who received lower numbers, demonstrating that irrelevant anchors influenced these estimates (Tversky & Kahneman, 1974). “Anchoring and adjustment” is one of three well-known heuristics described by Tversky and Kahneman (1974) in a classic paper that also describes the representativeness and availability heuristics. Like the other heuristics, anchoring and adjustment can be a useful way of making judgments. Imagine that you are trying to set a value on an antique chair that you have inherited from a distant aunt. You might recall seeing a very similar chair in slightly better condition at a local antique dealer.

/pdf/incorporating-the-irrelevant-anchors-in-judgments-of-belief-1adtichffw.pdf

心理学原理 = The principles of psychology

Citations

Pulsed out of awareness: EEG alpha oscillations represent a pulsed-inhibition of ongoing cortical processing

Disorders of memory

Attention and the subjective expansion of time.

Making Sense of Self-Esteem

Incorporating the Irrelevant: Anchors in Judgments of Belief and Value