scholarly journals Visually evoked EEG activity differentiates individuals during a perceptual categorization task but preparatory or late activity does not

2010 ◽  
Vol 9 (8) ◽  
pp. 799-799
Author(s):  
K. Das ◽  
S. Zhang ◽  
B. Giesbrecht ◽  
M. P. Eckstein
Keyword(s):  
Perceptual Categorization ◽  
Eeg Activity ◽  
Categorization Task

Two Categorical Stages of Object Recognition

Perception ◽  
1978 ◽  
Vol 7 (6) ◽  
pp. 695-705 ◽  
Author(s):  
Elizabeth K Warrington ◽  
Angela M Taylor
Keyword(s):  
Object Recognition ◽  
Left Hemisphere ◽  
Right Hemisphere ◽  
Visual Object ◽  
Visual Object Recognition ◽  
Perceptual Categorization ◽  
Categorization Task ◽  
Semantic Categorization ◽  
Tentative Model ◽  
The Right

Visual object recognition was investigated in a group of eighty-one patients with right- or left-hemisphere lesions. Two tasks were used, one maximizing perceptual categorization by physical identity, the other maximizing semantic categorization by functional identity. The right-hemisphere group showed impairment on the perceptual categorization task and the left-hemisphere group were impaired on the semantic categorization task. The findings are discussed in terms of categorical stages of object recognition. A tentative model of their cerebral organization is suggested.

Visual Recognition

2005 ◽  
Vol 16 (2) ◽  
pp. 152-160 ◽  
Author(s):  
Kalanit Grill-Spector ◽  
Nancy Kanwisher
Keyword(s):  
Object Recognition ◽  
Exposure Duration ◽  
Visual Recognition ◽  
Natural Images ◽  
Visual Object ◽  
Visual Object Recognition ◽  
Perceptual Categorization ◽  
Identification Task ◽  
Categorization Task ◽  
Processing Steps

What is the sequence of processing steps involved in visual object recognition? We varied the exposure duration of natural images and measured subjects' performance on three different tasks, each designed to tap a different candidate component process of object recognition. For each exposure duration, accuracy was lower and reaction time longer on a within-category identification task (e.g., distinguishing pigeons from other birds) than on a perceptual categorization task (e.g., birds vs. cars). However, strikingly, at each exposure duration, subjects performed just as quickly and accurately on the categorization task as they did on a task requiring only object detection: By the time subjects knew an image contained an object at all, they already knew its category. These findings place powerful constraints on theories of object recognition.

scholarly journals Initial Training With Difficult Items Facilitates Information Integration, but Not Rule-Based Category Learning

2008 ◽  
Vol 19 (11) ◽  
pp. 1169-1177 ◽  
Author(s):  
Brian J. Spiering ◽  
F. Gregory Ashby
Keyword(s):  
Category Learning ◽  
Information Integration ◽  
Random Order ◽  
Cognitive Skill ◽  
The Other ◽  
Perceptual Categorization ◽  
Initial Training ◽  
Rule Based ◽  
Categorization Task ◽  
Better Than

Previous research has disagreed about whether a difficult cognitive skill is best learned by beginning with easy or difficult examples. Two experiments that clarify this debate are reported. Participants in both experiments received one of three types of training on a difficult perceptual categorization task. In one condition, participants began with easy examples, then moved to examples of intermediate difficulty, and finished with the most difficult examples. In a second condition, this order was reversed, and in a third condition, participants saw examples in a random order. The results depended on the type of categories that participants were learning. When the categories could be learned via explicit reasoning (a rule-based task), the three training procedures were equally effective. However, when the categorization rule was difficult to describe verbally (an information-integration task), participants who began with the most difficult items performed much better than participants in the other two conditions.

Quantitative modeling of category learning in amnesic patients

2001 ◽  
Vol 7 (1) ◽  
pp. 1-19 ◽  
Author(s):  
J. VINCENT FILOTEO ◽  
W. TODD MADDOX ◽  
JENNIFER DUNCAN DAVIS
Keyword(s):  
Category Learning ◽  
Rule Learning ◽  
Brain Regions ◽  
Quantitative Model ◽  
Quantitative Modeling ◽  
Perceptual Categorization ◽  
Categorization Task ◽  
Model Based ◽  
The Brain ◽  
Model Based Analysis

Category rule learning was examined in two amnesic patients using the perceptual categorization task (e.g., Ashby & Gott, 1988; Filoteo & Maddox, 1999). Traditional accuracy-based analyses as well as quantitative model-based analyses were performed. Unlike accuracy-based analyses, the model-based approach allowed us to examine both categorization rule learning and variability in the trial-by-trial application of the participant's categorization rule. The results indicated that the amnesic patients were as accurate as the controls in learning a complex, nonlinear rule over a large number of trials. The model-based analysis indicated that, in general, the amnesic patients learned the categorization rule as well as controls and applied their rule as consistently as controls. Categorization performance on a second day of testing revealed that amnesic patients can retain the categorization rule over a 24-h period. These results suggest that the brain regions damaged in amnesia are not involved in category learning or memory for the category structures. (JINS, 2001, 7, 1–19.)

Variations Across the Menstrual Cycle in EEG Activity During Thinking and Mental Relaxation

1999 ◽  
Vol 13 (3) ◽  
pp. 163-172 ◽  
Author(s):  
R. Krug ◽  
M. Mölle ◽  
H.L. Fehm ◽  
J. Born
Keyword(s):  
Menstrual Cycle ◽  
Divergent Thinking ◽  
Spectral Power ◽  
Plasma Concentrations ◽  
Task Demands ◽  
Menstrual Phase ◽  
Convergent Thinking ◽  
Eeg Activity ◽  
Dimensional Complexity ◽  
Mental Relaxation

Abstract Previous studies have indicated: (1) peak performance on tests of divergent creative thinking during the ovulatory phase of the menstrual cycle; (2) compared to convergent analytical thinking, divergent thinking was found to be associated with a distinctly increased dimensional complexity of ongoing EEG activity. Based on these findings, we hypothesized that cortical information processing during the ovulatory phase is characterized by an increased EEG dimensionality. Each of 16 women was tested on 3 occasions: during the ovulatory phase, the luteal phase, and menses. Presence of the phases was confirmed by determination of plasma concentrations of estradiol, progesterone, and luteinizing hormone. The EEG was recorded while the women performed: (1) tasks of divergent thinking; (2) tasks of convergent thinking; and (3) during mental relaxation. In addition to EEG dimensional complexity, conventional spectral power analysis was performed. Behavioral data confirmed enhanced creative performance during the ovulatory phase while convergent thinking did not vary across cycle phases. EEG complexity was higher during divergent than convergent thought, but this difference remained unaffected by the menstrual phase. Influences of the menstrual phase on EEG activity were most obvious during mental relaxation. In this condition, women during the ovulatory phase displayed highest EEG dimensionality as compared with the other cycle phases, with this effect being most prominent over the central and parietal cortex. Concurrently, power within the alpha frequency band as well as theta power at frontal and parietal leads were lower during the luteal than ovulatory phase. EEG results indicate that task demands of thinking overrode effects of menstrual cycle. However, with a less demanding situation, an ovulatory increase in EEG dimensionality became prominent suggesting a loosening of associative habits during this phase.

Investigation of the Effect of Mode and Tempo on Emotional Responses to Music Using EEG Power Asymmetry

2013 ◽  
Vol 27 (3) ◽  
pp. 142-148 ◽  
Author(s):  
Konstantinos Trochidis ◽  
Emmanuel Bigand
Keyword(s):  
Left Hemisphere ◽  
Right Hemisphere ◽  
Emotional Responses ◽  
Interactive Effects ◽  
Eeg Activity ◽  
Musical Excerpt ◽  
Major Mode ◽  
Musical Modes ◽  
Slow Tempo ◽  
The Right

The combined interactions of mode and tempo on emotional responses to music were investigated using both self-reports and electroencephalogram (EEG) activity. A musical excerpt was performed in three different modes and tempi. Participants rated the emotional content of the resulting nine stimuli and their EEG activity was recorded. Musical modes influence the valence of emotion with major mode being evaluated happier and more serene, than minor and locrian modes. In EEG frontal activity, major mode was associated with an increased alpha activation in the left hemisphere compared to minor and locrian modes, which, in turn, induced increased activation in the right hemisphere. The tempo modulates the arousal value of emotion with faster tempi associated with stronger feeling of happiness and anger and this effect is associated in EEG with an increase of frontal activation in the left hemisphere. By contrast, slow tempo induced decreased frontal activation in the left hemisphere. Some interactive effects were found between mode and tempo: An increase of tempo modulated the emotion differently depending on the mode of the piece.

The association of age and aerobic activity history with 40-Hz EEG activity during cognitive challenge

1996 ◽  
Author(s):  
B. Hatfield ◽  
D. Santa Maria ◽  
T. Spalding ◽  
C. Blanchard ◽  
A. Haufler ◽  
...  
Keyword(s):  
Eeg Activity ◽  
Aerobic Activity ◽  
Cognitive Challenge ◽  
40 Hz
Sign in / Sign up

Export Citation Format

Share Document