Biomedical subjects

Jana Schaich Borg

Publications and source records attributed to Jana Schaich Borg.

4 recordsLinked to original sources

PubMed2006

Motor experience with graspable objects reduces their implicit analysis in visual- and motor-related cortex.

Motor-related regions of parietal and prefrontal cortices have been shown to selectively activate when observers passively view objects that afford manual grasping. Yet, it remains unknown whether these cortical responses depend on prior motor-related experience with the object being observed. To address this question, we asked participants to undergo fMRI scanning while viewing exemplars of two different categories of graspable objects: one associated with extensive motor experience (door knobs) and one associated with no self-reported motor experience (artificial rock climbing holds). Despite participants' lack of experience grasping climbing holds, these objects were found to generate a systematic response in several visuomotor-related regions of cortex-including left PMv and left AIP. Interestingly, however, the response to door knobs did not include activity in any motor-related regions, being limited instead to a comparatively small bilateral area of lateral occipital cortex, relative to the more spatially extensive response in occipital and temporal cortex that was observed for climbing holds. This result suggested that object-specific responses in both visual- and motor-related cortex may in fact negatively correlate with object-specific motor experience. To test this possibility, we repeated the experiment using participants having extensive self-reported experience grasping climbing holds (i.e., veteran indoor rock climbers). Consistent with our hypothesis, both climbing holds and door knobs generated activity limited to lateral occipital cortex. Taken together, these data support the proposal that repeated real-world motor experience with an object category may lead to reduced implicit analysis in both motor- and visual-related regions of cortex.

Adolescent↗

PubMed2006

Consequences, action, and intention as factors in moral judgments: an FMRI investigation.

The traditional philosophical doctrines of Consequentialism, Doing and Allowing, and Double Effect prescribe that moral judgments and decisions should be based on consequences, action (as opposed to inaction), and intention. This study uses functional magnetic resonance imaging to investigate how these three factors affect brain processes associated with moral judgments. We find the following: (1) Moral scenarios involving only a choice between consequences with different amounts of harm elicit activity in similar areas of the brain as analogous non-moral scenarios; (2) Compared to analogous non-moral scenarios, moral scenarios in which action and inaction result in the same amount of harm elicit more activity in areas associated with cognition (such as the dorsolateral prefrontal cortex) and less activity in areas associated with emotion (such as the orbitofrontal cortex and temporal pole); (3) Compared to analogous non-moral scenarios, conflicts between goals of minimizing harm and of refraining from harmful action elicit more activity in areas associated with emotion (orbitofrontal cortex and temporal pole) and less activity in areas associated with cognition (including the angular gyrus and superior frontal gyrus); (4) Compared to moral scenarios involving only unintentional harm, moral scenarios involving intentional harm elicit more activity in areas associated with emotion (orbitofrontal cortex and temporal pole) and less activity in areas associated with cognition (including the angular gyrus and superior frontal gyrus). These findings suggest that different kinds of moral judgment are preferentially supported by distinguishable brain systems.

Adolescent↗

PubMed2005

Placing a tool in the spotlight: spatial attention modulates visuomotor responses in cortex.

Visual spatial attention has long been associated with facilitatory effects on visual perception. Here, we report that spatial attention can also modulate implicit visuomotor processing in dorsal regions of human cortex. Participants underwent fMRI scanning while performing a voluntary attentional orienting task that varied the category of a task-irrelevant object in the attended location (tool vs. non-tool). Data were then analyzed as a function of the attended location (left vs. right visual field) and the object category in that location. We found that the fMRI BOLD response in two visuomotor-related regions--the supplementary motor area (SMA) and the left inferior parietal lobule (IPL)--showed an interaction between the location of attention and the location of the tool in the bilateral display. Further, these responses were statistically distinct from those regions in dorsal cortex showing activity modulated only by the tool location or only by the attended location. While the effects of attending non-foveally within the visual field have been well documented in relation to visual perception, our findings support the proposal that voluntary visuospatial attention may also have consequences for the implicit planning of object-directed actions.

Adult↗

PubMed2002

Acute handling stress modulates methylphenidate-induced catecholamine overflow in the medial prefrontal cortex.

Although stress is an extensively investigated phenomenon, the effects of specific stressors on the pharmacologic activity of routinely administered drugs are less well characterized. We designed the present study to investigate the effect of handling stress on catecholaminergic responsivity following an acute methylphenidate (MP, Ritalin) challenge in the medial prefrontal cortex (mPFC). Norepinephrine (NE) and dopamine (DA) levels were simultaneously measured in 15-min samples of PFC dialysate using HPLC coupled with electrochemical detection. Sprague-Dawley rats were handled for 15 min, which produced an increase from basal extracellular DA and NE levels. Handling stress attenuates the DA response when administered 2 h prior to IP MP, whereas handling stress enhances the DA response when administered simultaneously with IG MP. These findings suggest that persistent alterations in mesocorticolimbic DA-ergic activity are induced by a short exposure to restraint stress as evidenced by the altered response to MP challenge.

Acute Disease↗