FUNCTIONAL NEUROANATOMY OF EMOTION 341 Teasdale et al.(1999).Given its known cognitive func- tively.As a general rule,the studies included in this tions including modulation of attention and executive review controlled for activations driven by simple sen- functions,and interconnections with subcortical limbic sory pro ssing by designing both the target and con itive r condi ve con d with with sual stimuli).Often,the pictorial stimuli were matched tensetart matiae ele Mrr sonal event then self-induce or internally for color.luminance,and complexity across target and The sua stimuli that activated the ACC is consistently activated in semantic and ep- were ant memory retrieval tasks (Cabeza and Nyberg a/o 09.D yn et al ct a 1997 007 1998 2000-I ane et al 1999 Paradiso et al 1999:Simn 3.3 Recall induction.cognitive demand,and the in- et al.,2000:Kalin et al..1997:Irwin et al.1997). tivati Nearly 60%of recall indu pared otional faces (Morris et al,1998a;Sprengelmeyer et v .1998),an em tional films(Par .199 002)Iike the AcC ent als 1998- e with cognitively demanding emotional of the of tasks y ha either (1)fr m the :7.71,P=0.01),than with assive emo rocessing of emotionally loaded content or (2)from an tional tasks.Lane et al.(1997c)and Reiman et al. nteraction between visual perception and emotional all,but no find processing gement visua ds on-human 100 that the een propu nal et a/1997a:Beauregard et a/1998) periential or expressive aspects of internally ated emotions (Reiman et al., 1997).In a study in Reiman and colleagues (1997)suggested that visual association areas in occipitotemporal cortex could be which multiple specific individual emotions were in involved in the evalua proce ure duced by recall ppine 2000 10e und d to ho 1996:Lane etal.1997:Lang etal.1998:Reiman etal that these regior s are direct and indirect recinients of signals from the internal milieu and viscera. which are 1997).An alternative interpretation is that the occipi important in the regulation of homeostasis.Given this al cortex is recruited use the visual stim ar hly aro s sucn s proposed role of emotion in maintaining ho p ears to a Damas at these regions.》 epd .2000)Difrer gener ticularly semantic complexity.has been + and ne ern stat nay ren eural c elates as the underlying mediator of the occipital cortex acti- despite the con mental states known as feelings.Reiman et al.(1997) ations experimentally balancing for or,and had posited that the insula may nt of ima O participate in the (rwin et eval tion of distre sing cognitions. nteroceptive emotional significance an alarm cer nter nts tional and nal stimuli due to complexity.However,Lang et al.(1998) 1 demonstrated no difference in the duration or magni of scann ts st ally generated recalled emoti ons and orge e ublish re th with cognitively demanding tasks mov 3.4 Visual induction and the occipital cortex inital corte ble thu occipital/visual cortex (OC)(mainly BA 18 and 19.but tion to the activation found in the visual cortex also occipital gyrus and fusiform gyrus)was almos ticularly in the fusiform gyrus may arise from the ated by vis 60 ocative sti of presence of faces in the pictorial and film stimuli.How ction studies ep mpson e ral.(20 0 that the O a助 audito ere ctio di t thas re and sTeasdale et al. (1999). Given its known cognitive func￾tions including modulation of attention and executive functions, and interconnections with subcortical limbic structures, the ACC’s involvement in cognitive induc￾tion of emotional response, is not surprising. Such a process demands cognitive effort, as subjects are in￾structed to recall or imagine an emotionally laden per￾sonal event then self-induce or internally generate in￾tense target emotions (Teasdale et al., 1999). Moreover, the ACC is consistently activated in semantic and ep￾isodic memory retrieval tasks (Cabeza and Nyberg, 2000). 3.3 Recall induction, cognitive demand, and the in￾sula. Nearly 60% of recall induction studies reported activation of the insula, compared to less than 20% of either visual or auditory inductions (X2 8.23, P 0.02). Like the ACC, recruitment of the insula was also identified more with cognitively demanding emotional tasks (X2 7.71, P 0.01), than with passive emo￾tional tasks. Lane et al. (1997c) and Reiman et al. (1997) specifically found that emotional recall, but not emotional film viewing, engaged the insula. Our find￾ings as well as earlier studies on non-human primates (Augustine et al., 1996) support the suggestion that the insula is preferentially involved in the evaluative, ex￾periential, or expressive aspects of internally gener￾ated emotions (Reiman et al., 1997). In a study in which multiple specific individual emotions were in￾duced by recall (happiness, sadness, fear, and disgust), Damasio and colleagues (2000) found that all emotions engaged the cingulate, insular cortex, and brainstem. Their findings are consistent with anatomic evidence that these regions are direct and indirect recipients of signals from the internal milieu and viscera, which are important in the regulation of homeostasis. Given this proposed role of emotion in maintaining homeostasis, Damasio et al. (2000) suggest that these regions, while engaged in the recall and self-generation of affect, monitor the ongoing internal emotional state of the organism, and may represent the neural correlates of mental states known as feelings. Reiman et al. (1997) had posited that the insula may participate in the evaluation of “distressing cognitions, interoceptive emotional significance” as an alarm center for inter￾nally-sensed dangers or homeostatic changes. Such an internal alarm hypothesis is consistent with our find￾ings that the insula is associated with both self-in￾duced or internally generated recalled emotions and with cognitively demanding tasks. 3.4 Visual induction and the occipital cortex. The occipital/visual cortex (OC) (mainly BA 18 and 19, but also occipital gyrus and fusiform gyrus) was almost exclusively activated by visually evocative stimuli. Of the 35 visual induction studies, 60% reported activa￾tion in the OC, which were reported in only 29% and 0% of recall and auditory induction studies, respec￾tively. As a general rule, the studies included in this review controlled for activations driven by simple sen￾sory processing by designing both the target and con￾trol conditions to have similar sensory loads (e.g., con￾ditions with emotionally laden visual stimuli were compared with conditions with emotionally neutral vi￾sual stimuli). Often, the pictorial stimuli were matched for color, luminance, and complexity across target and control conditions. The visual stimuli that activated OC were diverse and included pleasant and aversive pictures (Kosslyn et al., 1996; Lane et al., 1997a; Lang et al., 1998; Reiman et al., 1997; Taylor et al., 1998, 2000; Lane et al., 1999; Paradiso et al., 1999; Simpson et al., 2000; Kalin et al., 1997; Irwin et al., 1997), emotional faces (Morris et al., 1998a; Sprengelmeyer et al., 1998), and emotional films (Paradiso et al., 1997; Lane et al., 1997c; Beauregard et al. 1998). The modu￾lation of the OC by the emotional components of visual induction may have been driven by either (1) from the processing of emotionally loaded content or, (2) from an interaction between visual perception and emotional processing. Due to its engagement across multiple visual emo￾tion tasks, it has been proposed that the OC mediates and appraises visually relevant, complex emotional stimuli (Lane et al., 1997a; Beauregard et al., 1998). Reiman and colleagues (1997) suggested that visual association areas in occipitotemporal cortex could be involved in the evaluation procedure of complex visual stimuli with emotional relevance. The activations in the visual cortex were found to be independent of the type of emotions by a number of authors (Kosslyn et al., 1996; Lane et al., 1997; Lang et al., 1998; Reiman et al., 1997). An alternative interpretation is that the occipi￾tal cortex is recruited because the visual stimuli are highly arousing, as such stimuli appears to activated perceptual areas more extensively (Lang et al., 1998; Taylor et al., 2000). Differences in image complexity, particularly semantic complexity, has been proposed as the underlying mediator of the occipital cortex acti￾vations despite experimentally balancing for the con￾tent of images for luminance, color, and detail (Irwin et al., 1997; Taylor et al., 2000). For example, visual cor￾tex activation may also be attributed to differential eye movements between emotional and non-emotional stimuli due to complexity. However, Lang et al. (1998) demonstrated no difference in the duration or magni￾tude of scanning eye movements between the stimuli, and Lorge et al. (2000; unpublished data) reported that the extent of eye movements did not correlate with occipital cortex responses. Another possible contribu￾tion to the activation found in the visual cortex, par￾ticularly in the fusiform gyrus, may arise from the presence of faces in the pictorial and film stimuli. How￾ever, Simpson et al. (2000) found that the OC activa￾tion in their study was related to the emotional valence of the pictures not the presence of faces, and suggested FUNCTIONAL NEUROANATOMY OF EMOTION 341