نگرش های ناکارآمد در اختلال عاطفی فصلی

Research examining dysfunctional attitudes in Seasonal Affective Disorder (SAD) has produced contrasting results. The present study sought to resolve this contradiction by addressing some methodological problems of the previous studies. The study examined dysfunctional attitudes using the Dysfunctional Attitudes Scale (DAS) in individuals with SAD and never-depressed controls. The SAD group were tested both when depressed in the winter (Time 1) and during their remission period (Time 2). At Time 1 the SAD group displayed a relatively elevated DAS compared to controls and to their Time 2 scores. These data therefore provide potential support for a view that SAD is characterized by underlying dysfunctional attitudes.

Clinical shifts in affective response across the different seasons have been classified in the DSM-IV (APA, 2000) as Recurrent Mood Disorder with Seasonal Pattern, a condition also known as Seasonal Affective Disorder (SAD). SAD is characterized by a pattern of Major Depressive Episodes that recur in the autumn and winter and remit in the summer. There are established differences between SAD and nonseasonal depression in terms of symptom profile (with, for example, SAD being characterized by reversed neurovegetative symptoms such as hypersomnia and increased appetite, and nonseasonal depression being typically associated with early morning waking and reduced appetite) and treatment of choice (phototherapy for SAD and psychological or pharmacotherapy for nonseasonal depression) (Dalgleish, Rosen, & Marks, 1996). However, recent research suggests that SAD and nonseasonal depression may also differ in terms of their cognitive profile (Dalgleish, Spinks, Golden, & du Toit, 2004; Dalgleish, Spinks, Kuyken, & Yiend, 2001; Levitan, Rector, & Bagby, 1998; Rohan, Sigmon, & Dorhofer, 2003). In particular, patients with SAD do not seem to show either the usual depressotypic mood-congruent memory bias for negative words (Dalgleish et al., 2004) or the usual difficulty that depressed individuals have in accessing specific autobiographical memories when cued (Dalgleish et al., 2001). It has been proposed that such biases in underlying cognitive processes in nonseasonal depression are a function of underlying depressogenic dysfunctional beliefs or schemas (Beck, Rush, Shaw, & Emery, 1979). On this basis, it has been argued that the pattern of null results across certain cognitive measures in SAD is a sign that the disorder is not characterized by such underlying dysfunctional beliefs (Dalgleish, Spinks, Golden, & du Toit (2004) and Dalgleish, Spinks, Yiend, & Kuyken (2001)). Recent data from Rohan et al. (2003) speak directly to this ‘differential schemas’ hypothesis. They presented SAD patients with a number of cognitive measures including the Dysfunctional Attitudes Scale (DAS; Weissman & Beck, 1978). The DAS is a widely used measure of underlying depressotypic attitudes or schemas. For example, “I cannot be happy unless most people I know admire me”. Many studies have reported higher DAS scores (reflecting more depressotypic attitudes) in nonseasonally depressed groups compared to controls (e.g. Peselow, Robins, Block, Barouche, & Fieve, 1990). However, Rohan et al. (2003) found no significant difference between SAD participants and controls on the DAS when administered in the autumn/winter. On the face of it, these autumn/winter data of Rohan et al. (2003) are consistent with the hypothesis that SAD is not characterized by the same patterns of depressotypic attitudes or schemas found in nonseasonal depression and therefore offer support to the differential schemas hypothesis (Dalgleish et al., 2004). Indeed, Rohan et al. (2003) concluded: “the schemas involved in SAD may be different from those found in nonseasonal depression and, hence, not adequately captured by the DAS” (p. 28). If reliable, this finding would have potential clinical implications as it would suggest that aspects of cognitive therapy for depression, that target certain dysfunctional schemas, may have relatively less purchase for individuals with SAD and this may need to be taken into account when further developing psychological treatments for the seasonal version of the disorder—for which the initial results have been promising (Rohan et al., 2003; Rohan, Tierney Lindsey, Roecklein, & Lacy, 2004). However, there are at least two sources of concern regarding the DAS findings of Rohan et al. (2003). The first is that the SAD patients had a history of the disorder, rather than being currently in episode. Indeed, only 12 out of 18 SAD participants were in episode at the time of autumn/winter testing. The second is that data from a previous study by Hodges and Marks (1998) indicated that SAD patients who were currently in episode did show higher DAS scores than nondepressed controls. However, a potential problem with the Hodges and Marks (1998) study is that SAD diagnosis was not established using a structured clinical interview. It is therefore possible that some of the SAD group were in fact patients with nonseasonal depression and that this might account for the depressotypic profile on the DAS. Given the potential theoretical and clinical importance of understanding the nature of dysfunctional attitudes in SAD (Dalgleish et al., 2004), it seems important to try and clarify these contrasting data regarding the DAS in SAD samples, especially as there are methodological concerns regarding both of the previous studies (Hodges & Marks, 1998; Rohan et al., 2003). The first aim of the current study was therefore to compare DAS scores from a group of SAD participants currently in episode, and diagnosed using a structured clinical interview, with those of a group of never-depressed controls. A secondary aim of the current study was to include a longitudinal component to investigate whether DAS scores in the summer were lower than those in the autumn/winter in the SAD group (as was found by Rohan et al., 2003) and to explore the within-participant stability of DAS scores across autumn/winter and summer.