Limits...
Top-down modulation of visual processing and knowledge after 250 ms supports object constancy of category decisions.

Schendan HE, Ganis G - Front Psychol (2015)

Bottom Line: N3 impoverishment effects localized to both prefrontal and occipitotemporal cortex for real objects only.The N3 also showed knowledge effects by 230 ms that localized to occipitotemporal cortex.Finally, response activity in supplementary motor area during a posterior SW after 900 ms showed impoverishment effects that correlated with RTs.

View Article: PubMed Central - PubMed

Affiliation: School of Psychology, Cognition Institute, University of Plymouth Plymouth, UK.

ABSTRACT
People categorize objects more slowly when visual input is highly impoverished instead of optimal. While bottom-up models may explain a decision with optimal input, perceptual hypothesis testing (PHT) theories implicate top-down processes with impoverished input. Brain mechanisms and the time course of PHT are largely unknown. This event-related potential study used a neuroimaging paradigm that implicated prefrontal cortex in top-down modulation of occipitotemporal cortex. Subjects categorized more impoverished and less impoverished real and pseudo objects. PHT theories predict larger impoverishment effects for real than pseudo objects because top-down processes modulate knowledge only for real objects, but different PHT variants predict different timing. Consistent with parietal-prefrontal PHT variants, around 250 ms, the earliest impoverished real object interaction started on an N3 complex, which reflects interactive cortical activity for object cognition. N3 impoverishment effects localized to both prefrontal and occipitotemporal cortex for real objects only. The N3 also showed knowledge effects by 230 ms that localized to occipitotemporal cortex. Later effects reflected (a) word meaning in temporal cortex during the N400, (b) internal evaluation of prior decision and memory processes and secondary higher-order memory involving anterotemporal parts of a default mode network during posterior positivity (P600), and (c) response related activity in posterior cingulate during an anterior slow wave (SW) after 700 ms. Finally, response activity in supplementary motor area during a posterior SW after 900 ms showed impoverishment effects that correlated with RTs. Convergent evidence from studies of vision, memory, and mental imagery which reflects purely top-down inputs, indicates that the N3 reflects the critical top-down processes of PHT. A hybrid multiple-state interactive, PHT and decision theory best explains the visual constancy of object cognition.

No MeSH data available.


Multiple-state interactive (MUSI) theory and summary of results. Numerals indicate time in milliseconds (ms). (A) Brain regions contributing to each state of cortical dynamics. Brain images in black box taken from impoverishment effects in fMRI studies of Ganis et al. (2007) for state 2 and dorsal stream of state 1 and Schendan and Stern (2008) for all others. Note: Green arrow is feedback. Black arrow is bottom-up. State 1 axial slice shows object-sensitive areas. VLPFC, ventral lateral prefrontal cortex; vcIPS, ventrocaudal intraparietal sulcus; TOS, transverse occipital sulcus; LOS, lateral occipital sulcus; ITS, inferotemporal sulcus; FG, fusiform gyrus; COS, collateral sulcus; LP, lateral inferior parietal cortex; MPF, medial prefrontal cortex; PCC, posterior cingulate cortex; ACC, anterior cingulate cortex; SMA, supplementary motor area. (B) Timing of cortical dynamics and summary of ERP and RT results. In state 1, the VPP/N170 in occipitotemporal cortex (see A) shows no impoverished-real-object effect. In state 2, the N3 complex (including N300, P3, P250, D220, N250 components), indexing an interactive network of occipitotemporal, occipitoparietal, and VLPFC regions (see A), shows the earliest impoverished-real-object effect. The later N400 also shows such an effect. In state 3, the P600/LPC in temporal lobe parts of a default mode network (see A) shows a later impoverished-real-object effect; note, the sLORETA brain source results from Figure 8E are copied here to show the location of P600/LPC effects. The latest such effect modulates an anterior slow wave (SW) in the PCC (see A). Gray shading indicates time course of the brain source of the P600 and SW impoverishment effects. A final posterior SW (pSW; state final) correlates with RTs and reflects SMA. Gray arrow points to mean RTs along ERP time course (same legend as for ERPs).
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4584963&req=5

Figure 11: Multiple-state interactive (MUSI) theory and summary of results. Numerals indicate time in milliseconds (ms). (A) Brain regions contributing to each state of cortical dynamics. Brain images in black box taken from impoverishment effects in fMRI studies of Ganis et al. (2007) for state 2 and dorsal stream of state 1 and Schendan and Stern (2008) for all others. Note: Green arrow is feedback. Black arrow is bottom-up. State 1 axial slice shows object-sensitive areas. VLPFC, ventral lateral prefrontal cortex; vcIPS, ventrocaudal intraparietal sulcus; TOS, transverse occipital sulcus; LOS, lateral occipital sulcus; ITS, inferotemporal sulcus; FG, fusiform gyrus; COS, collateral sulcus; LP, lateral inferior parietal cortex; MPF, medial prefrontal cortex; PCC, posterior cingulate cortex; ACC, anterior cingulate cortex; SMA, supplementary motor area. (B) Timing of cortical dynamics and summary of ERP and RT results. In state 1, the VPP/N170 in occipitotemporal cortex (see A) shows no impoverished-real-object effect. In state 2, the N3 complex (including N300, P3, P250, D220, N250 components), indexing an interactive network of occipitotemporal, occipitoparietal, and VLPFC regions (see A), shows the earliest impoverished-real-object effect. The later N400 also shows such an effect. In state 3, the P600/LPC in temporal lobe parts of a default mode network (see A) shows a later impoverished-real-object effect; note, the sLORETA brain source results from Figure 8E are copied here to show the location of P600/LPC effects. The latest such effect modulates an anterior slow wave (SW) in the PCC (see A). Gray shading indicates time course of the brain source of the P600 and SW impoverishment effects. A final posterior SW (pSW; state final) correlates with RTs and reflects SMA. Gray arrow points to mean RTs along ERP time course (same legend as for ERPs).

Mentions: The time when ERPs show the impoverished-real-object effect defines when PHT and decision processes contribute to the visual constancy of category decisions based on knowledge, not just sensory evidence. To infer the timing of cortical sources, ERP results were integrated with fMRI location information by both estimating the ERP sources and relating similar functional patterns between methods (Luck, 1999). To use vision and decision theories to predict the ERP effects, this report capitalizes on the multiple-state interactive (MUSI) account of the brain basis of visual object cognition to define the times and scalp sites to analyze (Schendan and Kutas, 2003, 2007a; Schendan and Maher, 2009; Schendan and Ganis, 2012). This framework proposes that posterior object processing areas activate at multiple times in brain “states” serving distinct functions. This account extends the principle that different brain areas can perform different functions for cognition at different points in time because bottom-up, feedback, and recurrent activity alters neuronal computations, as demonstrated, for example, in visual area V1 (Lamme and Roelfsema, 2000). Likewise, object-sensitive areas perform different functions in perception and cognition due to different neural computations associated with bottom-up, feedback, and recurrent activity (Schendan and Lucia, 2010).


Top-down modulation of visual processing and knowledge after 250 ms supports object constancy of category decisions.

Schendan HE, Ganis G - Front Psychol (2015)

Multiple-state interactive (MUSI) theory and summary of results. Numerals indicate time in milliseconds (ms). (A) Brain regions contributing to each state of cortical dynamics. Brain images in black box taken from impoverishment effects in fMRI studies of Ganis et al. (2007) for state 2 and dorsal stream of state 1 and Schendan and Stern (2008) for all others. Note: Green arrow is feedback. Black arrow is bottom-up. State 1 axial slice shows object-sensitive areas. VLPFC, ventral lateral prefrontal cortex; vcIPS, ventrocaudal intraparietal sulcus; TOS, transverse occipital sulcus; LOS, lateral occipital sulcus; ITS, inferotemporal sulcus; FG, fusiform gyrus; COS, collateral sulcus; LP, lateral inferior parietal cortex; MPF, medial prefrontal cortex; PCC, posterior cingulate cortex; ACC, anterior cingulate cortex; SMA, supplementary motor area. (B) Timing of cortical dynamics and summary of ERP and RT results. In state 1, the VPP/N170 in occipitotemporal cortex (see A) shows no impoverished-real-object effect. In state 2, the N3 complex (including N300, P3, P250, D220, N250 components), indexing an interactive network of occipitotemporal, occipitoparietal, and VLPFC regions (see A), shows the earliest impoverished-real-object effect. The later N400 also shows such an effect. In state 3, the P600/LPC in temporal lobe parts of a default mode network (see A) shows a later impoverished-real-object effect; note, the sLORETA brain source results from Figure 8E are copied here to show the location of P600/LPC effects. The latest such effect modulates an anterior slow wave (SW) in the PCC (see A). Gray shading indicates time course of the brain source of the P600 and SW impoverishment effects. A final posterior SW (pSW; state final) correlates with RTs and reflects SMA. Gray arrow points to mean RTs along ERP time course (same legend as for ERPs).
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4584963&req=5

Figure 11: Multiple-state interactive (MUSI) theory and summary of results. Numerals indicate time in milliseconds (ms). (A) Brain regions contributing to each state of cortical dynamics. Brain images in black box taken from impoverishment effects in fMRI studies of Ganis et al. (2007) for state 2 and dorsal stream of state 1 and Schendan and Stern (2008) for all others. Note: Green arrow is feedback. Black arrow is bottom-up. State 1 axial slice shows object-sensitive areas. VLPFC, ventral lateral prefrontal cortex; vcIPS, ventrocaudal intraparietal sulcus; TOS, transverse occipital sulcus; LOS, lateral occipital sulcus; ITS, inferotemporal sulcus; FG, fusiform gyrus; COS, collateral sulcus; LP, lateral inferior parietal cortex; MPF, medial prefrontal cortex; PCC, posterior cingulate cortex; ACC, anterior cingulate cortex; SMA, supplementary motor area. (B) Timing of cortical dynamics and summary of ERP and RT results. In state 1, the VPP/N170 in occipitotemporal cortex (see A) shows no impoverished-real-object effect. In state 2, the N3 complex (including N300, P3, P250, D220, N250 components), indexing an interactive network of occipitotemporal, occipitoparietal, and VLPFC regions (see A), shows the earliest impoverished-real-object effect. The later N400 also shows such an effect. In state 3, the P600/LPC in temporal lobe parts of a default mode network (see A) shows a later impoverished-real-object effect; note, the sLORETA brain source results from Figure 8E are copied here to show the location of P600/LPC effects. The latest such effect modulates an anterior slow wave (SW) in the PCC (see A). Gray shading indicates time course of the brain source of the P600 and SW impoverishment effects. A final posterior SW (pSW; state final) correlates with RTs and reflects SMA. Gray arrow points to mean RTs along ERP time course (same legend as for ERPs).
Mentions: The time when ERPs show the impoverished-real-object effect defines when PHT and decision processes contribute to the visual constancy of category decisions based on knowledge, not just sensory evidence. To infer the timing of cortical sources, ERP results were integrated with fMRI location information by both estimating the ERP sources and relating similar functional patterns between methods (Luck, 1999). To use vision and decision theories to predict the ERP effects, this report capitalizes on the multiple-state interactive (MUSI) account of the brain basis of visual object cognition to define the times and scalp sites to analyze (Schendan and Kutas, 2003, 2007a; Schendan and Maher, 2009; Schendan and Ganis, 2012). This framework proposes that posterior object processing areas activate at multiple times in brain “states” serving distinct functions. This account extends the principle that different brain areas can perform different functions for cognition at different points in time because bottom-up, feedback, and recurrent activity alters neuronal computations, as demonstrated, for example, in visual area V1 (Lamme and Roelfsema, 2000). Likewise, object-sensitive areas perform different functions in perception and cognition due to different neural computations associated with bottom-up, feedback, and recurrent activity (Schendan and Lucia, 2010).

Bottom Line: N3 impoverishment effects localized to both prefrontal and occipitotemporal cortex for real objects only.The N3 also showed knowledge effects by 230 ms that localized to occipitotemporal cortex.Finally, response activity in supplementary motor area during a posterior SW after 900 ms showed impoverishment effects that correlated with RTs.

View Article: PubMed Central - PubMed

Affiliation: School of Psychology, Cognition Institute, University of Plymouth Plymouth, UK.

ABSTRACT
People categorize objects more slowly when visual input is highly impoverished instead of optimal. While bottom-up models may explain a decision with optimal input, perceptual hypothesis testing (PHT) theories implicate top-down processes with impoverished input. Brain mechanisms and the time course of PHT are largely unknown. This event-related potential study used a neuroimaging paradigm that implicated prefrontal cortex in top-down modulation of occipitotemporal cortex. Subjects categorized more impoverished and less impoverished real and pseudo objects. PHT theories predict larger impoverishment effects for real than pseudo objects because top-down processes modulate knowledge only for real objects, but different PHT variants predict different timing. Consistent with parietal-prefrontal PHT variants, around 250 ms, the earliest impoverished real object interaction started on an N3 complex, which reflects interactive cortical activity for object cognition. N3 impoverishment effects localized to both prefrontal and occipitotemporal cortex for real objects only. The N3 also showed knowledge effects by 230 ms that localized to occipitotemporal cortex. Later effects reflected (a) word meaning in temporal cortex during the N400, (b) internal evaluation of prior decision and memory processes and secondary higher-order memory involving anterotemporal parts of a default mode network during posterior positivity (P600), and (c) response related activity in posterior cingulate during an anterior slow wave (SW) after 700 ms. Finally, response activity in supplementary motor area during a posterior SW after 900 ms showed impoverishment effects that correlated with RTs. Convergent evidence from studies of vision, memory, and mental imagery which reflects purely top-down inputs, indicates that the N3 reflects the critical top-down processes of PHT. A hybrid multiple-state interactive, PHT and decision theory best explains the visual constancy of object cognition.

No MeSH data available.