We used filtered low spatial frequency images of facial emotional expressions (angry, fearful, happy, sad, or neutral faces) that were blended with a high-frequency image of the same face but with a neutral facial expression, so as to obtain a "hybrid" face image that "masked" the subjective perception of its emotional expression. Participants were categorized in three groups of participants: healthy control participants (N = 49), recovered previously depressed (N = 79), and currently depressed individuals (N = 36), All participants were asked to rate how friendly the person in the picture looked. Simultaneously we recorded, by use of an infrared eye-tracker, their pupillary responses. We expected that depressed individuals (either currently or previously depressed) would show a negative bias and therefore rate the negative emotional faces, albeit the emotions being invisible, as more negative (i.e., less friendly) than the healthy controls would. Similarly, we expected that depressed individuals would overreact to the negative emotions and that this would result in greater dilations of the pupil's diameter than those shown by controls for the same emotions. Although we observed the expected pattern of effects of the hidden emotions on both ratings and pupillary changes, both responses did not differ significantly among the three groups of participants. The implications of this finding are discussed.

Participants viewed "hybrid" faces that showed a facial expression (anger, fear, happiness, or sadness) only in the lowest spatial frequency (1-6 cycles/image), which was blended with the same face's neutral expression in the rest of the bandwidth (7-128 cycles/image). Participants rated the portrayed persons (compared to neutral images) as "friendly" when the lowest spatial frequencies showed a positive expression and "unfriendly" when the lowest spatial frequencies showed negative expressions. In contrast, the same hybrid images were explicitly judged as neutral and their "hidden" emotional expressions could not be explicitly recognized, as also confirmed by d' sensitivity measures. Finally, one patient (SS) who had the left anterior temporal lobe surgically resected (including the amygdala), failed to show the above described unconscious effects on friendliness judgments when viewing "afraid" and "sad" hybrid faces. We conclude that the lowest spatial frequencies of facial expressions can evoke "core" emotions without knowledge or awareness of a specific emotion but these core emotions can convey a clear "impression" of a person's character.

Previous research has shown that during recognition of frontal views of faces, the preferred landing positions of eye fixations are either on the nose or the eye region. Can these findings generalize to other facial views and a simpler perceptual task? An eye-tracking experiment investigated categorization of the sex of faces seen in four views. The results revealed a strategy, preferred in all views, which consisted of focusing gaze within an ‘infraorbital region’ of the face. This region was fixated more in the first than in subsequent fixations. Males anchored gaze lower and more centrally than females.

Parents of monozygotic twins typically learn to recognise their own children and also to tell them apart on photographs. However, it is unknown whether such exemplar expertise can be generalised to unfamiliar faces of equal similarity (ie other twins). In the present study, parents of monozygotic twins were compared to 'control' parents whose children were non-twin siblings. In a same/different task with familiar and unfamiliar twin faces as stimuli, twins' parents were faster than control parents in distinguishing their own children, but slower when distinguishing unfamiliar twin faces. These unexpected findings can be interpreted as a generalisation of a habitual perceptual strategy that is efficient only with familiar face exemplars. When pictures of the twins' faces were inverted by 180degrees, the typical inversion costs for familiar faces were observed, but the twins' parents recognised unfamiliar twins' faces better when these were inverted than when upright. This inverted inversion effect could be caused by the high similarity of the face pairs as well as by experience with familiar faces of equally high similarity. We conclude that the facial expertise of twins' parents is idiosyncratic to their own children and not based on an enhanced general facial expertise.

The University of Tromsø is situated in the town of Tromsø in Norway (69.4 N) and it is the world’s northernmost university. Hence, the Cognitive Science Laboratory of the Department of Psychology at the University of Tromsø is also the world’s northernmost laboratory of its kind. The University of Tromsø is the fourth and most recent university to be established in Norway. The department of Psychology is also relatively ‘‘young’’ (being established in 1983) and a rather international group of researchers and teachers have formed or currently form our departmental staff. Collectively, our academic backgrounds originate from various universities in Norway as well as from Belgium, Britain, Canada, Chile, Finland, France, Germany, Italy, the Netherlands, Sweden, and the USA. Among the various parallel projects that are currently run in the cognitive science laboratory, some do take advantage of the geographical location of the university by dealing with the effect of ‘‘extreme’’ latitudes and unusual seasonal patterns of daylight on cognitive and perceptual processing (e.g., Brennen et al. 1999; Brennen 2001). However, our interests, taken collectively, span a rather wide range of topics revolving around key questions in cognitive science, like attention (and its disorders: spatial neglect, ADHD), memory, visual imagery, perception of objects and faces, comprehension and learning, and the organization of knowledge. Moreover, a range of methods are currently used to address the above themes, e.g., studies of brain-damaged patients, eye-tracking, computational modeling, human operant conditioning, and classic cognitive/behavioral methods. The cerebral basis of spatial vision

We examined clinically depressed (CD; n = 16), previously depressed (PD; n = 19) and never depressed (ND; n = 18) individuals on 13 theoretically selected Rorschach (Exner, 1993; Rorschach, 1942) variables and on the Beck Depression Inventory (BDI; Beck, Rush, Shaw, & Emery, 1979). The group assignment was made according to the criteria of Diagnostic and Statistical Manual of Mental Disorders (4th ed.; American Psychiatric Association, 1994). We tested 2 contradictory models for depressive vulnerability, Beck's (Clark & Beck, 1999) and Miranda and Persons's (1988; Persons & Miranda, 1992), in a planned comparison design with focused contrasts. The CDs significantly contrasted the combined group of NDs and the PDs in a pathological direction on 8 of the 13 Rorschach variables and on the BDI. However, the combined group of CDs and PDs also significantly contrasted the NDs in a pathological direction on 3 of these Rorschach variables and on the BDI. In addition, logistic regression analyses indicated that Rorschach indexes significantly improved the prediction of major depression above and beyond that achieved by the BDI. The findings show that the Rorschach method was able to identify (a) cognitive and aggressive disturbances that are present in individuals who are actively depressed but not in individuals who have been depressed in the past or never been depressed and (b) affective and coping disturbances that are present in depressed individuals and to some degree in PD individuals but not in individuals who have not experienced depression. We discuss the scanty evidence of psychological disturbances in PD individuals, as measured with the Rorschach, in relation to the mood-state dependent hypothesis of Miranda and Persons (1988; Persons & Miranda, 1992).