Covert attention enhances fine spatial discrimination (orientation d′) within the foveola with high selectivity across 20′ separations¶

Claim · All claims
Evidence · 1 study (2 entries) · causal r1 · q3
Currency · newest study 2017 · not yet checked against its sources · not reviewed by a person · overdue for a recheck since 2022: baselines and conditions change

Subclaims¶

q3 i? In a foveolar orientation-discrimination cueing task, d′ was significantly higher in valid than neutral and invalid trials, and reaction times were faster in valid trials. → Poletti Martina 2017 q3 i? The cost of attending the wrong location was similar whether that location fell in the same or opposite hemifield as the target (p=0.83), showing selectivity even within one hemifield at 20′ separation. → Poletti Martina 2017 (2)

Evidence¶

Poletti Martina 2017¶

Poletti Martina, Rucci Michele, Carrasco Marisa. (2017). Selective attention within the foveola. Nature Neuroscience. https://doi.org/10.1038/nn.4622

q3 · i? · causal · r1

Experiment 3: five observers reported the tilt of a tiny bar at one of four boxes 14′ from fixation under a central cue. The article also reports faster reaction times in valid trials (ANOVA F(2,4) = 51; p<0.0001) and significant individual-level differences for all observers.

"discrimination accuracy, expressed as the index of sensitivity d′, was significantly higher in the valid trials, when the cue correctly predicted the target location, than in the neutral and invalid trials (ANOVA F(2,4) = 49.9; p<0.0001)"

Poletti Martina 2017 (2)¶

Poletti Martina, Rucci Michele, Carrasco Marisa. (2017). Selective attention within the foveola. Nature Neuroscience. https://doi.org/10.1038/nn.4622

q3 · i? · causal · r1

Same Experiment 3 analysis comparing invalid-cue costs across hemifield configurations; the article concludes "attentional shifts retained a very high degree of selectivity even for locations separated by only 20′ within the same hemifield."

"the cost resulting from focusing attention at the “wrong” location was similar, irrespective of whether this location fell within the same or opposite hemifield as the target (Fig. 3B–C, p=0.83 two-tailed paired t-test)"

Discussion¶

Related Claims¶

• Covert attention facilitates detection within the foveola at locations only 20 arcminutes apart, with an effect similar in magnitude to the parafovea
• Fine foveolar attentional effects persist during normal, non-stabilized fixation with natural retinal image motion
• Endogenous spatial cueing speeds detection at the attended parafoveal location and slows it at the unattended location — related
• Detection is slower for targets within the foveola than in the parafovea despite equal detectability — related
• Normal sense organs possess surplus discriminative efficiency beyond ordinary practical demands — related